Ⅱ. 单项填空 (共15小题; 每小题1分, 满分15分)
21. The reason ___________his success was _______he worked very hard.
A. for; why B. for; that
C. why; that D. why; how
【解析】选B。考查句型The reason for. . . is/was that. . . 。此处使用介词for的原因是其后接名词短语his success。故B项正确。
【举一反三】
The reason __________he succeeded in passing the exam is
___________he worked very hard.
A. for; why B. for; that
C. why; that D. why; how