21． He would have led ________ peaceful life instead of changing his lifestyle if he had not met his former classmate by ________ chance.
A．the; a B．a; the
C．a; / D．/; the
答案：C 考查固定搭配。句意：如果他没有偶遇老同学的话，他可能会过着安宁的生活，而不会改变生活方式。lead a peaceful life固定搭配，过着安宁的生活；by chance固定搭配，偶然地，意外地，故选C。
22． I think you ________ very badly toward your mother.
A．observed B．respected
C．behaved D．performed
答案：C 考查动词词义辨析。句意：我认为你对待你妈妈的态度很恶劣。observe观察，注意；respect尊敬，敬仰；perform表演，(成功地)表现，完成；behave举动，(行为或举止)表现，符合句意，故选C。
23． All we need ________ a small piece of land where we can plant various kinds of fruit trees throughout the growing seasons of the year.
A．are B．was
C．is D．were
答案：C 考查主谓一致和动词时态。根据表语a small piece of land可知谓语用单数，而根据从句的时态可知所填词用一般现在时，故选C项。
