第二部分：英语知识运用（共两节，满分45分）
第一节：单项填空（共15小题；每小题1分，满分15分）
从A、B、C、D四个选项中，选出可以填入空白处的最佳选项，并在答题卡上将该项涂黑。
21. The thief took off his shoes when he slipped into the house in order to steal something ___.
A. unnotice B. unnoticed C. unnoticing D. to unnotice
22. Once we discover a mistake, we should not _____ it but correct it immediately, to create better conditions for economic development.
A. ignore B. postpone C. deny D. sheltered
23. It’s said that there are plenty of hotels in that town. There _____ be any difficulty for you to find one to stay
