1. This experiment turned out to be _______ failure, but as we know, success often comes after _______ failure.
A. a; a B. 不填；不填 C. a; 不填 D. 不填; a
2. —— I’d like the report to be ready by six.
—— _____.
A. Why not B. Just as you wish, sir C. Yes, sir D.I am afraid so.
3. ----- Is Bob still performing?
----- I’m afraid not. He is said _______ the stage already as he has become an official.
A. to have left B. to leave C. to have been left D. to be left
