._____________ he used to go skiing in winter but now swimming is his favorite.
| A．At a time | B．At one time | C．At no time | D．At times |
Her father told her to be careful when _____ the street. 
| A．he is crossing | B．she is crossing | C．crossed | D．crossing |
Hardly ________ home when he was asked to go back to work. 
| A．had he arrived | B．he had arrived | C．did he arrive | D．he arrived |
My key is gone. Have you seen it anywhere? 
– Oh, it is in the room _______ we had a talk last night
| A．that | B．which | C．where | D．what |
She was admitted to so excellent ________ university that her parents were proud of her.
| A．/ | B．a | C．an | D．the |
I’ m sorry. I can’ t give you the telephone number without Mr. Smith’s______.(合肥市)
| A．permission | B．allowing | C．agreement | D．performance |