Relative Clauses Advanced

Respuesta correcta: A) who

• A) whowho is correct because it introduces a defining relative clause about a person, and the guide is the subject of knows.
• B) whichwhich introduces defining clauses about things, not people, so it cannot refer to the guide here.
• C) wherewhere introduces a relative clause of place, such as the market where they sell fruit, not a person.
• D) whosewhose introduces possession, like the student whose father is a doctor, so it does not fit with knows.

Respuesta correcta: C) The quetzal, which lives in Monteverde, is easy to spot.

• A) The quetzal, which lives in Monteverde is easy to spot.A non-defining clause needs a comma after which and before the main verb, so this version closes the clause wrongly.
• B) The quetzal which lives in Monteverde, is easy to spot.Without an opening comma this reads as a defining clause about the bird, and the extra comma after it is misplaced.
• C) The quetzal, which lives in Monteverde, is easy to spot.This works because a non-defining clause about the bird is set off by a pair of commas around the whole clause.
• D) The quetzal lives in Monteverde, which is easy to spot.Here which has no clear antecedent, so the sentence wrongly suggests that spotting the bird is the easy part.

Respuesta correcta: B) The teacher who explained the volcano project retired in June.

• A) The teacher, which explained the volcano project, retired in June.which with paired commas would make the clause non-defining and also refers to a person, so it is wrong here.
• B) The teacher who explained the volcano project retired in June.who is correct because it is the subject of explained in this defining clause about the teacher.
• C) The teacher whom explained the volcano project retired in June.whom is the object form and cannot act as the subject of explained, so this clause has no subject.
• D) The teacher explained the volcano project retired in June.Dropping the pronoun leaves no verb slot for explained, so the sentence breaks into two unlinked parts.

Respuesta correcta: D) It identifies which of the trees were planted.

• A) It names the kind of tree that was planted.Naming the kind would need a noun such as native after trees, not a verb clause with its own object.
• B) It explains why the students decided to plant more trees.A reason clause would use because, while this clause has a subject and a verb, so it identifies instead of explaining.
• C) It identifies the students who did the planting.Students is the agent of were planted, but this clause describes the trees, not the people who planted them.
• D) It identifies which of the trees were planted.This works because which restricts the noun trees to a specific subset: the ones standing on the riverbank.

Respuesta correcta: A) Professor Ramirez, whose office is on the third floor, teaches geology.

• A) Professor Ramirez, whose office is on the third floor, teaches geology.whose introduces possession inside a non-defining clause set off by two commas, which suits this extra detail.
• B) Professor Ramirez teaches geology, who his office is on the third floor.who his office has no verb after the pronoun, so the relative clause is broken and the information is misplaced.
• C) Professor Ramirez, who his office is on the third floor, teaches geology.A clause with who needs a subject and a verb, but who his office is not a full clause, so it cannot work.
• D) Professor Ramirez, whom his office is on the third floor, teaches geology.whom is the object form and would need an object after it, so it cannot stand in this subject position.

Respuesta correcta: B) The gym whose roof is still green will open in June.

• A) The gym whose is next to the field will open in June.whose must be followed by the noun that is owned, such as roof, so leaving it with only a verb breaks the clause.
• B) The gym whose roof is still green will open in June.whose is correct here because roof is the possessed noun and is still green describes that roof.
• C) The gym who roof is still green will open in June.who introduces a clause about a person, and this gym is a building, so who cannot show possession.
• D) The gym where the roof is still green will open in June.where introduces a clause of place, such as where the children train, not possession of a roof.

Respuesta correcta: D) It is a defining clause that identifies which teacher wrote the exam and takes no commas.

• A) It is a non-defining clause, because it can be removed without changing the meaning.Removing the clause would leave an unidentified teacher, so the information is essential and the clause is defining.
• B) It is an object clause, because who receives the action of wrote.who is the subject of wrote, not its object, and a relative clause is not called an object clause here.
• C) It is a defining clause that needs commas on both sides to be complete.Defining clauses about people take no commas, and adding commas here would wrongly add extra information.
• D) It is a defining clause that identifies which teacher wrote the exam and takes no commas.This is correct because the clause restricts the noun to one specific teacher and carries no comma at all.

Respuesta correcta: A) They mark the clause as extra comment, not part of the core fact about the weather.

• A) They mark the clause as extra comment, not part of the core fact about the weather.This is the right reason: paired commas turn the clause into a non-defining comment about an already named place.
• B) They show that Monteverde is the place where the visitors come from.where would describe a place inside the clause, but this clause talks about visitors and surprise, not location.
• C) They are needed because the clause describes a person rather than a thing.The clause describes the weather, not a person, so the commas are not marking a shift to human reference.
• D) They can be removed without changing which place the sentence is about.Removing the commas would not remove the comment, it would only force the clause to become a defining one.

Respuesta correcta: C) It restricts the noun, telling us which bus among many is meant.

• A) It adds a comment that could be deleted with no loss of meaning.A deletable comment would need paired commas, and without them the clause here is part of the core meaning.
• B) It tells us where the bus is at the moment of speaking.Place would need where, for example the bus that waits near the terminal, so this is not about location.
• C) It restricts the noun, telling us which bus among many is meant.This is correct because the clause selects one bus out of many, which is exactly what a defining clause does.
• D) It explains why the bus takes that particular route.A reason would need because or so, and this clause has its own subject and verb with no link word.

Respuesta correcta: B) The two students who won the national science fair did so in Cartago last month.

• A) The two students which won the national science fair, they won it in Cartago.which never refers to people, and the extra subject they turns one relative clause into two broken parts.
• B) The two students who won the national science fair did so in Cartago last month.This works because who stays as the subject of won, and did so avoids repeating the verb in a long sentence.
• C) The two students, that won the national science fair, won it in Cartago.that cannot be used between commas in a non-defining clause, and this clause needs no commas at all.
• D) The two students whom won the national science fair won it in Cartago.whom is an object pronoun, so it cannot be the subject of won in this defining clause about students.

Respuesta correcta: C) which is wrong because the antecedent is a thing but the clause refers to people.

• A) which is wrong because the clause describes a place rather than an object.The clause refers to customers, who are people, so where is wrong here and which is not being judged on place.
• B) which is wrong because the clause must have no subject of its own.A relative clause normally has its own subject and verb, so refusing one subject would rule out almost every clause.
• C) which is wrong because the antecedent is a thing but the clause refers to people.This is the right reading: which refers to things, and here the customers inside the clause are people.
• D) which is wrong because a relative clause can never follow the noun it describes.Relative clauses follow the noun they describe all the time, so the position is standard and not the problem.

Respuesta correcta: A) The library, which lends laptops, is open until nine.

• A) The library, which lends laptops, is open until nine.This works because a comma before and after which turns the clause into an extra comment about a known library.
• B) The library lends laptops, and students use them for research.Two joined clauses with and is a good rewrite of the meaning, but the question asks for a non-defining relative clause.
• C) The library that lends laptops is open until nine.that without commas keeps the clause defining, so this version still restricts which library is meant.
• D) The library where students study lends laptops until nine.where would describe a place inside the library, but here the clause describes an action, not a location.

Respuesta correcta: D) Without commas the clause would be grammatically complete but logically empty.

• A) Without commas the clause identifies one specific shop, not every shop in Liberia.This is correct: the shop is narrowed to one particular shop, and removing the clause would change what is meant.
• B) Without commas the clause adds background news that the reader may ignore.Background news belongs in a non-defining clause between commas, so that reading contradicts the missing commas.
• C) Without commas the clause explains the reason my aunt left the capital.A reason would need because or so, and this clause has its own subject and verb with no link word.
• D) Without commas the clause would be grammatically complete but logically empty.The clause is not empty, it names the bags, so treating it as logically empty ignores real information.

Respuesta correcta: B) The road, which crosses the hills, is closed on Sundays.

• A) The road crosses the hills, and the road is closed on Sundays.This repeats road twice in a short sentence, which is clumsy when a single relative clause can do the job.
• B) The road, which crosses the hills, is closed on Sundays.This works because the comma-free clause is defining and the subject appears only once at the start of the sentence.
• C) The road that the hills it crosses is closed on Sundays.A contact clause cannot add a second subject like it, so the clause ends up with two subjects and no verb.
• D) The road is closed on Sundays, which the hills are steep that day.Here which has no clear antecedent and the clause trails off, so the reader cannot tell what is being described.

Respuesta correcta: C) The mural that covers the wall was painted by local artists.

• A) The mural, who covers the wall, was painted by local artists.who introduces a clause about a person, but a mural is a painting, so the pronoun does not match the antecedent.
• B) The mural where covers the wall was painted by local artists.where introduces a clause of place, but this clause has a verb and describes what the mural does, not where it is.
• C) The mural that covers the wall was painted by local artists.This works because that is correct for a defining clause about a thing and it carries no commas in this version.
• D) The mural whose covers the wall was painted by local artists.whose needs a possessed noun after it, so leaving the pronoun with only a verb makes the clause incomplete.

Respuesta correcta: D) The problem is that who reads as the subject of the main clause instead of the subject of the clause.

• A) Nothing is wrong, because who correctly introduces the clause about caring.who is already the correct pronoun here, and this version ignores the real ambiguity between the two verbs.
• B) The problem is that who should be replaced by whom because lives follows it.whom would be the object form and would need a noun after it, so swapping it in would not fix the reading.
• C) The problem is only that the sentence needs commas around the clause.The clause is defining, so it needs no commas. Adding them would only turn it into an optional comment.
• D) The problem is that who reads as the subject of the main clause instead of the subject of the clause.This is the right reading: who can belong to lives or to cares, so the clause should be reworded to remove the doubt.

Respuesta correcta: B) The team from Puntarenas trained hard, and that effort paid off in the final match.

• A) The team from Puntarenas trained hard because the final match paid off.because would claim that the final match caused the training, which reverses the meaning of the original sentence.
• B) The team from Puntarenas trained hard, and that effort paid off in the final match.This works because that effort carries the second idea, so no relative pronoun is needed at all.
• C) The team from Puntarenas trained hard while the final match paid off for nobody.while would suggest the two events ran in parallel, and adding for nobody changes the result entirely.
• D) The team from Puntarenas trained hard, and the final match paid off instead of them.instead of them would mean the match replaced the team, which is not what the original comment says.

Respuesta correcta: C) The workshop, which starts at eight, may still have space, so the student should ask early.

• A) The workshop starts at eight, that has space, so the student should ask early.Two commas do not create a clause here, and that cannot open a second clause after a comma in standard English.
• B) The workshop starts at eight and whether it has space, which the student still needs to ask.whether introduces a yes or no question as a clause, and this version leaves the sentence without a main verb.
• C) The workshop, which starts at eight, may still have space, so the student should ask early.This works because which plus commas makes a clean non-defining clause and the main verb is the finite may have.
• D) Whether the workshop that starts at eight has space, the student asked in Grecia.Fronting whether leaves no main verb at the end, so the question clause cannot replace the sentence on its own.

Respuesta correcta: A) The house overlooking the bay has a large solar roof.

• A) The house overlooking the bay has a large solar roof.This works because a reduced relative clause keeps the active participle overlooking and the subject appears only once.
• B) The house overlooks the bay, and it has a large solar roof.This is grammatically fine, but it repeats the subject twice, which is exactly what the clause is meant to avoid.
• C) The house is overlooking the bay, having a large solar roof.A passive -ing form after is is not standard English, and having after it would be a second dangling participle.
• D) The house that the bay it overlooks has a large solar roof.A contact clause cannot take a second subject like it, so the clause ends up with two subjects and no verb.

Respuesta correcta: D) The engineer who designed the bridge left the country last week.

• A) The engineer, which designed the bridge, left the country last week.which is reserved for things, and the paired commas would wrongly present the detail as an optional comment.
• B) The engineer whom designed the bridge left the country last week.whom is the object form and needs an object after it, so this version has a clause without a subject.
• C) The engineer whose designed the bridge left the country last week.whose needs a possessed noun after it, so leaving it directly before a verb leaves the clause unfinished.
• D) The engineer who designed the bridge left the country last week.This works because who is the subject of designed and no commas are needed for a defining clause about a person.