I.

1.It is difficult to learn English.

2.It is interesting to understand different cultures and ways of life

3.It was wonderful to see our friends again.

4.It is useless to complain about the matter now.

5.It was very comfortable to sit in one place for so long.

6.We heard Mr.Brown parking his car near the gate.

7.Do you see a hen run bout the yard?

8.Everyone saw the boy jumps into the river.

9.Have you ever seen James drive a truck?

10.The principal noticed those pupils try harder and harder.

II.

1....going to the seaside this summer?

2....to invite our friends on Sundays?

3...giving me a hand?

4....staying at home for a change?

5....going for a ride?

6....to meet her last week

7.... saying goodbye to anyone.

8....reading books to watching television.

9....good to ask him for help.