II: 20, D
III: 21, B→reading
22, B→who sings
23, B→not to spend
24, C→than
25, B→natural resources
IV: 26, C
27, B
28, A
29, B
30, A
V: 31, That old house has just been sold
32, Although the weather was bad, they had a wonderful holiday
33, A new more will be built here
34, If he doesn't take this pills, he won't be better
35, Althought he works hard, he can't support his large family
VI: 36, If it doesn't rain tomorrow, I will go camping with my friends
37, If I met the ailen from outer space, I would invite it to go home and talk
38, I have never travelled by air
39, The students are studying for the exam now
40, It was such a cold day that we decided not to go out
41, If I were you, I would learn harder