第一节 完形填空(共10小题；每小题2分，满分20分)
阅读下面短文，掌握其大意，然后从21～30各题所给的A、B、C和D项中，选出最佳选项，并在答题卡上将该项涂黑。
I am discovering that many people want, above all else, to live life fully. But sometimes the past prohibits our living and enjoying life to the utmost in the present.
A school teacher 21 his room a few minutes early and 22 a mealworm laboriously crawling along the floor. It had somehow been 23 . The back part of the worm was dead and dried up, but still attached to the 24 living part by just a thin thread.
