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，并在答题卡上将该选项涂黑。
21. ---- Just a moment. I haven’t finished packing my suitcase.
---- _______ . It’s high time we left for the airport.
A. Go ahead B. Take it easy C. Hurry up D. That’s fine
22. ----If you don’t bring a birthday present to Lucy, you may________.
----Thank you for reminding me. Surely I’ll buy her one this evening.
A. leave her alone B. let her down
C. hold her back D. cheer her up
23. Most birds find it safe to sleep in the trees, but _______ they have eggs or young chicks, they don’t use a nest.
A. why B. how C. unless D. where
