Now one of the most serious problems many people are worried about _____ on the lack of adequate housing space.
| A．insists | B．depends | C．agrees | D．focuses |
Some of the heat near the surface of the earth _____ electricity.
| A．is used to making | B．are used for making |
| C．is used to make | D．are used to make |
_______we’ll go camping tomorrow depends on the weather.
| A．If | B．Whether | C．That | D．Where |
It worried her a bit_______her hair was turning grey.
| A．while | B．what | C．if | D．that |
As we all know, Asia is_______ Europe.
| A．four times the size of | B．the size four times of |
| C．four times the size as | D．four times as the size of |
Tom_______two of his classmates_______invited to the party.
| A．as well as; was | B．as good as; were | C．and; have | D．as well; has been |