He doesn’t feel very tied after the heavy work, because he is used to ______ for hours without a rest.
| A．work | B．working | C．works | D．worked |
Ladies and gentlemen, please ______ seated until the plane has come to a complete stop.
| A．remain | B．keep | C．go | D．get |
Please do me a favor —______ my friend Mr. Smith to Youth Theater at 7:30 tonight.
| A．to invite | B．inviting | C．invite | D．invited |
______ herself with other girls, she feels she is quite lucky.
| A．Comparing | B．Compared | C．To compare | D．Being compared |
— Lovely weather, isn’t it?
— Yes, a bit hot, ______.
| A．although | B．but | C．though | D．yet |
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 |