— I wonder how much you charge for your services．
— The first two are free _______the third costs $30．
| A．while | B．until | C．when | D．before |
The Mekong River Commission has found no evidence ______ the dams on the upper reaches have an influence on the water flow downstream．
| A．which | B．that | C．where | D．what |
Head coach Li Yan bursts into tears of joy when she sees Zhou Yang first _____ the finish line at the women's 1500m short track speed skating final．
| A．to cross | B．having crossed | C．cross | D．crossed |
27．It was the President himself______ opened the door．
| A．who | B．when | C．which | D．where |
The actor still remembers the excitement in his class when a female classmate _____ for a key role in a Zhang Yimou film．
| A．is chosen | B．s chosen | C．chooses | D．chose |
What's your opinion of Mr．Li's request that we ______ spend half an hour reading English aloud every morning?
| A．would | B．should | C．must | D．could |