Canada has vast areas of wilderness, from the Arctic north, _______ average winter temperatures are usually -20 0C, to the border with the USA in the south, _______ is said to be the longest border in the world not defended.
| A．which, where | B．whose, which | C．where, where | D．where, which |
Unluckily, when I dropped in, Dr. Smith ____, so we only had time for a few words.
| A．was just leaving | B．has just left | C．had just left | D．just left |
It rained heavily in the south, __________ serious flooding in several provinces.
| A．causing | B．having caused | C．caused | D．to cause |
Sam ________ some knowledge of the computer just by watching others working on it.
| A．brought up | B．looked up | C．picked up | D．set up |
Was it in the village ______ we used to live in _________ the accident happened?
| A．that; where | B．which; that | C．where; that | D．which; where |
A severe earthquake ________ Ya'an on April,20th, which has claimed 193deaths up to
now.
| A．attacked | B．hitted | C．knocked | D．struck |