二．单项选择（共20小题, 每小题1分，满分20分）
21. Some of the exercises appear to be ___ ones that you have done, but after taking ____ second look, you will find that they are different.
A．/; the B．the ; the C．the; a D．the; /
22．---You look troubled.
--- The director asked me to finish this task by Sunday. How can I ____ to?
A．attempt B．manage C．decide D．happen
