Ⅱ 语言知识及应用
阅读下面短文，掌握其大意，然后从21~30各题所给出的A,B,C和D项中，选出最佳选项，并在答题卡上将该项涂黑。
Before a master of performance performed, his pupil told him that his shoelace (鞋带) was loose. The master nodded, __21__ him, and then squatted (蹲下) down to tie it carefully.
After his pupil turned round, he again squatted down and __22__ his shoelace.
