IV.Choose the best answer. 1.My mother used to tell me stories_______________ I went to bed. A.since B.until C.before 2.You better take the keys_______________________ I’m not out. A.in case B.since C.after 3.My mother like eating fried chicken______________ it’s very bad for his health. A.because B.although C.when 4.Yesterday, Jim was playing the piano_____________his sister was playing the flute A.as B.although C.while 5.You shouldn’t spend too much on computer_____________ it is harmful to your eyes. A.as B.when C.although 6.I will phone you ___________________ I get there. A.while B.as soon as C.untill 7.The scientist usually works in his lab____________ the sun sets. A.untill B.as soon as C.although 8.____________you promise not to tell lies again, I won’t forgive you. A.If B.Even If C.Unless 9._____________her legs were hurt, she made attempt to finish the running track. A.Even If B.As if C.Unless 10.She talked_____________ she witnessed the accident. But in fact she knew nothing. A.as if B.even though C.even If