1. He was surprised at making a mistake

3. They insist on go to the circus

4. I don't mind helping Mom

5. She dislike awful work 

6. They enjoy reading book

7. She is busy with cooking 

8. I look forward to seeing you

9. He always thinks about swimming

1/ He made a mistake. He was surprised

⇒ He was surprised at making a mistake.

2/ I am reading. I am interested.

⇒  I'm interested in reading.

3/ The children want to go to the circus. They insist on it.

⇒ They insist on going to the circus.

4/ I do a lot of housework to help Mom. I don't mind it.

⇒ I don't mind helping Mom with a lot of work.

5/ She has to do that awful work. She dislikes it

⇒ She dislikes that awful work.

6/ My children read books. They enjoy it.

⇒ My children enjoy reading books.

7/ She is cooking. She is busy with it.

⇒ She is busy cooking.

8/ I want to see you. I look forward to it.

⇒ I look forward to seeing you.

9/ I like going swimming. I always think about it.

⇒ He always thinks about swimming.

10/ They don't like working. They are tired.

⇒ They don't like working because they are tired.

                               _Quynh_