Errors in the use of relative pronouns

Correct the following sentences.

1. Jack, ................................. is my friend, is a good boy.

2. Last year we visited Shimla ........................................ is perhaps the best hill station in India.

3. This is the house .................................... I purchased from Peter.

4. We bought some grapes from ................................... we extracted juice.

5. He lent me a mattress on ................................. I slept soundly.

6. I have a friend .................................... mother works at a bank.

7. With ...................................... were you exchanging pleasantries?

8. We met a traveler .................................... bag was stolen.

9. Air, ..................................... is present everywhere, is essential for the existence of life.

10. Please try to understand ................................... I say.

1. Jack, who is my friend, is a good boy. (That cannot be used in non-identifying relative clauses.)

2. Last year we visited Shimla which is perhaps the best hill station in India. (That is not used in non-identifying relative clauses.)

3. This is the house which I purchased from Peter. (We use which for things; who/whom for people.)

4. We bought some grapes from which we extracted juice.

5. He lent me a mattress on which I slept soundly.

6. I have a friend whose mother works at a bank.

7. With whom were you exchanging pleasantries?

8. We met a traveler whose bag was stolen. (Whose is the possessive form of who; who’s means who is or who has.)

9. Air, which is present everywhere, is essential for the existence of life.

10. Please try to understand what I say.