语知识运用第一节：单项填空从A、B、C、D四个选项中，选出可以填入空白处的最佳选项。21. —Tom, it is your turn to give us anEnglish lecture.—I told one yesterday.

Why are you staring at me—You look stupid! The way you wear is _______ annoys othersmost.

If this magazine is not yours, ____ can it be

What’s up? You look worried.Well,I_____on the problem for 5 hours but I haven’t got a single clue

________ do you read English books—About three times a week.