第二部分 英语知识运用(共两节,满分35分) 第一节 单项填空(共15小题;每小题1分,满分15分) 21. Students should be encouraged to use ___ Internet as ____ resource. A. 不填;a B. 不填;the C. the; the D. the; a 22. He found it increasingly difficult to read, ____ his eyesight was beginning to fail. A. though B. for C. but D. so 举一反三: The day breaks,______ the birds are singing. A. because B. as C. since D. for 解析:D。若选A、B、C,强调The day breaks(天亮)的直接原因或者显而易见的原因就是the birds are singing(鸟叫),显然这是不成立的,只有for引出的句子作为一种附加说明才成立。