( )20. —There's too much salt in our diet sometimes.
—So there is. The WHO says only 1.5 grams of salt \underline{\qquad} for each man every day.
A. is needed
B. needs
C. will need
D. has needed

A

( )21. —Can you tell me how to make apple juice?
—Sure. Please watch carefully and you will see how it ______.
A. is made
B. is making
C. makes
D. will make

A

( )22. —Look! How dirty the river looks!
—So it is. Things will be better if people ______ throwing rubbish into it.
A. are stopped
B. were stopped
C. stopped
D. will stop

A

( )23. —I won't come to the party unless Sue ______ too.
—You mean if Sue comes you'll come?
A. will invite
B. invites
C. invited
D. is invited

D

( )24. —What a nice garden!
—So it is. It ______ every day.
A. is cleaning
B. has cleaned
C. must clean
D. is cleaned

D

( )25. —Alice, you ______ on the phone.
—I'm coming. Thanks.
A. want
B. are wanted
C. are wanting
D. have wanted

B

Ⅲ. 完形填空。
Many scientists say that the world is getting hotter and hotter. If they are right, the ice at the North and the South Pole will melt eventually. If this \underline{26}, the sea will rise and may cover most \underline{27} all of Singapore. This will force everybody to move to a \underline{28} country.
We know that the sun \underline{29} the earth. The heat from the sun hits the \underline{30}, and some of it goes \underline{31} into the sky. However, factories and cars \underline{32} a lot of carbon dioxide (二氧化碳). When the gas rises into the sky, the heat from the sun can come \underline{33} them but the heat from the ground cannot. It \underline{34} near us in the sky and makes the \underline{35} hotter and hotter every year.
Scientists call this the "greenhouse effect" because a greenhouse is a small glass \underline{36} which is hot inside. It is used for \underline{37} plants in cool countries. Many countries are \underline{38} about the greenhouse effect. They are trying to stop factories and cars from sending \underline{39} gases into the sky. Scientists are not sure when the world will \underline{40} much hotter. Some people say that the greenhouse effect has started already and has begun to affect the world's weather.
( )26. A. happens B. falls C. changes D. shows
( )27. A. of B. or C. but D. and
( )28. A. higher B. larger C. safer D. farther
( )29. A. looks B. covers C. circles D. heats
( )30. A. ground B. space C. forest D. plants
( )31. A. out B. back C. off D. of
( )32. A. make B. process C. produce D. form
( )33. A. through B. over C. into D. toward
( )34. A. hides B. continues C. follows D. stays
( )35. A. cloud B. air C. season D. temperature
( )36. A. building B. flat C. tool D. machine
( )37. A. putting B. storing C. guarding D. growing
( )38. A. excited B. disappointed C. worried D. pleased
( )39. A. dangerous B. harmful C. heavy D. useful
( )40. A. prove B. polish C. get D. stop

A
; B
; C
; D
; A
; B
; C
; A
; D
; B
; A
; D
; C
; B
; C