142.(　 )We will have no water to drink_____ we don’t protect the earth. (2010上海市)

　　　　　　 A. until　　 B. before　　 C. though　　 D. if

141.(　 ) In summer, food goes bad easily ______ it is put in the refrigerator. (2010山西省)

　　　　　　 A. until　　 B. if　　　 C. unless

140.(　 ) In fact, China is one of the 13 thirstiest countries _____ it has the world’s third largest water supply(可用量)。(2010山东临沂市)

　　　　　 A. until　　 B. if　　 C. though　　　 D. because

139.(　 ) I bought my son a birthday present, _______ he liked it very much.

(2010山东聊城市)

　　　　　 A. or　　 B. but　　　 C. and　 D. so

138.(　 ) ---- Emma failed her exams. I think she should work harder.

　　　　 ---- I agree. _______ she does, she’ll get good grades. (2010湖北襄樊市)

　　　　　 A. If　　　 B. Because　　　 C. Before　　 D. Though

137.(　 ) I like watching CCTV 10 ______ I can learn a lot from it(2010黑龙江绥化市)

　　　　 A. if　　　 B. because　　　 C.　 though

136.(　 ) ---- I’m not sure _____ there are living things on the planets or not.

　　　　 ---- Even scientists aren’t sure about it. (2010福建福州市)　

　　　　　 A. whether　　　　 B. where　　　　 C. why

135.(　 ) - May I go to the concert with you?

　　　　　 - I’m afraid not ____ you have a ticket, because I have only one. (2010贵州铜仁)

　　 A. since　　　 B. if　　　　 C. unless　　　　 D. though

134.(　 ) ---- I don’t think your uncle really likes drama series.

　　　　　 ---- No, _______ he still watches the programme. (2010江苏南京)

　　　　　 A. and　　　 B. so　　 C. or　　 D. but

133.(　 ) --- Could we play football in your playground, Sir?

　　　　 --- No, ______ you have the principal’s note. (2010江苏扬州)

　　　　 A. if　　　 B. unless　　　 C. because　　 D. since