I. Give the correct form of the word in brackets.
1.Why dont you try these shops? They always offer_______ prices. (compete)
2.To protect our environment, industrial factories must stop releasing________ into the atmosphere. (pollute)
3.The red squirrel is now virtually____________ in England. (extinction) 
4.Things have been going badly at work__________. (recent)
5.The rainforests are being systematically_________. (destroy)
6.I missed the bus this morning.______,I had some money with me to get a taxi. (lucky)
7.Smoking is__________prohibited in public places in this country. (strict)
8.Coal, gas and oil are________forms of energy that can not be replaced after used. (renew)
9.Fossil fuels will be exhausted within a_________ short time. (relative)
10.A man was being questioned in connection with her___________. (disappear)
11.He likes reading books because it helps to___________ his knowledge. (wide)
12.People are encouraged to use solar energy because its supply is____________ and infinite. (limit)
13.We usually ask interviewees to_________________a few simple tasks on the computer to test their aptitude.
(performance)
14.The______________ in the Asian Games come from all over Asia. (participate)
15.I took a______________supply of games to keep the children amused. (plenty)
16.One of the good things about teaching young children is their______________. (enthusiast)
17.We need something to keep the children___________ in their summer holiday. (occupy)
18, The books are__________into different categories according to subject. (classify)
19.Confidence is the key to_____________.(succeed)
20.The room was littered with__________newspapers. (discard)