Global warming Period 6　Summing Up，Learning Tip and Assessment

4.______ the greenhouse effect，the earth ______ ______ about thirty－three degrees celsius ______ ______ ______ ______.
5.the ______ ______ of carbon dioxide ______ that more heat energy is trapped in the atmosphere ______ the ______ ______ ______ ______ ______.
6.it was ______ ______ ______ charles keeling ______ made ______ ______ ______ the amount of carbon dioxide in the atmosphere from 1957 to 1997.
7.they also believe ______ ______ the burning of more and more fossil fuels that is ______ ______ this increase in carbon dioxide.
8.there are some very different ______ among scientists ______ ______ ______.
9.sometimes i feel that ______ can't have any ______ ______ ______ huge ______ problems.
10.finally and most ______，talk ______ your family and friends ______ global warming and tell them what you have learned.
11.remember—your ______ ______.
part 4　multiple choice
1.is it ______ to you that the government is having a hard time now?
a.of much important　　　　　　　 　b.of much consequence
c.of very importance                 d.of much consequent
2.something must be done to ______ the river from ______.
a.stop；being polluted             b.stop；polluting
c.prevent；pollution               d.keep；polluted
3.there ______ quantities of apples in the basket and there was ______ milk in the bucket.
a.were；a number of                 b.was；quantities of
c.was；a good many                 d.were；a quantity of
4.______ we get good weather it will be a successful holiday.which is wrong?
a.so long as                 b.provided that
c.so long                   d.on condition that
5.—go for a picnic this weekend，ok?
—______.i love getting close to nature.
a.i don't think so                  b.i believe not
c.i couldn't agree more             d.i am afraid not
6.—now，where is my purse?