21. I expected to see her and was surprised by her ________.
A. existence B. absence C. entrance D. acceptance
22. You probably have been in such a situation ________ you are asked to help a foreign friend.
A. which B. as C. where D. why
23. How hard the athletes work now will ________ how they perform in the Olympics.
A. determine B. analyze C. monitor D. educate
24. My advice is that you should think about ________ you know anyone who fits your target audience.
A. which B. what C. that D. whether
25. — The more you practice, the more ________ you become.
— Sure. This is true of every type of skill.
A. innocent B. confident C. ignorant D. constant
26. You can set the table. ________, I’ll start making dinner.
A. Meanwhile B. Somehow C. Otherwise D. However
27. — Are you going to stay overnight?
— Not ________ it’s absolutely necessary.
A. when B. once C. since D. unless
