He determined to teach in a western province, though he _______in the city for a better life.
| A．could stay | B．would stay | C．could have stayed | D．had stayed |
—Where did you find Mr. Brown? —It was in the factory ______ he paid a visit yesterday.
| A．to which | B．that | C．which | D．to where |
Generally speaking, _____ according to the directions, the drug has no side effect.
| A．when taking | B．when taken |
| C．when to take | D．when to be taken |
If you are travelingthe customs are really foreign to your own，please do as the Romans do.
| A．in which | B．what | C．when | D．where |
The American Civil War lasted four yearsthe North won in the end.
| A．after | B．before |
| C．when | D．then |
How long is it ______ we last spent the holiday in the country together?
| A．until | B．before | C．that | D．since |