I often have conversations with John over telephone, while keep in touch with Tom by__________ letter.
| A．不填;;the | B．不填;a | C．the;不填 | D．the; a |
The door opened and in ________.
| A．rushed they | B．the children rushed | C．they rushed | D．did the children rush |
______ nobody was very enthusiastic about it, they decided to cancel the trip.
| A．See that | B．Seeing that | C．So | D．When |
I think our boat can pass the treacherous water ______ cautiously handled.
| A．until | B．if | C．lest | D．with |
The engineers are going on with their highway project, _____the expenses have risen.
| A．even though | B．just because | C．now that | D．as though |
The fuel must have been finished, ____ the engine stopped.
| A．since | B．as | C．because | D．for |