1.Give the correct form of the following

1.We (not eat) vegetables if they are poisonous and inedible

2.If solar energy is used widely in the future , the environment (be) protected

3.People will save natural resouces if thry (replaces) gas, oil and coal by solar energy

4.If you (use) energy-saving bulbs , you will spend less money on lighting

5.If Tam tried harder , he (win) the contest

6.Their parents would be happy if they (pass) the final exam

7.If you don't know how to swim , you (have) to be careful with water

8.If i had time , i (help) the poor children with studying

9.If i saw a UFOs , i ( not be) surprised

10.What you ( do) if you met an alien

11. If there (be) no gravity , you do not weigh anything

12.Waht activities the students (join) in if they are on vacation

13.If you (do) a report , you'll have to prepare it carefully

14.If Hoa (call) home , she'll tell her parents about her result

15.If we (be) on a spaceship , we would see the oceans , the big rivers and the tall mountains