It is believed that on December 21st, 1891, the first basketball game in _____ history was played．Then in 1936 in Berlin, it became _____ Olympic event.
| A．不填; an | B．a; an | C．the; the | D．不填; the |
Everything was placed exactly ________ it used to be before she left the laboratory.
| A．why | B．when |
| C．where | D．though |
________ I'm mistaken, I've seen that tall man at a party before.
| A．If | B．As |
| C．Unless | D．When |
Beijing is ranked first in terms of traffic jams and expenses for culture ________ Guangzhou is more open to peasant workers than Beijing and Shanghai.
| A．when | B．since |
| C．while | D．because |
________ he stops driving himself like this, he'll have a breakdown.
| A．Until | B．Once |
| C．Since | D．Unless |
________ my teacher didn't tell me directly, I still felt that I didn't live up to her expectation.
| A．When | B．Since |
| C．As | D．While |