No one ____ this building without the permission of the police.
| A．is leaving | B．is to leave | C．has left | D．will be leaving |
Luckily, we’d brought a road map without ______ we would have lost our way.
| A．it | B．that | C．this | D．which |
Is this the reason _______ at the meeting for his carelessness in his work？
| A．he explained | B．what he explained | C．how he explained | D．why he explained |
In the office I never seem to have time until after 5：30 pm, _____ many people have gone home.
| A．that | B．which | C．whose time | D．by which time |
All of the flowers now raised here have developed from those _______ in the forest.
| A．once they grew | B．they grew once | C．they once grew | D．once grew |
Our company will move to a tall building _______ we worked two years ago.
| A．where | B．when | C．that | D．which |