Just because they make more money than I do, _____ they seem to look down on me.
| A．so | B．and | C．while | D．不填 |
________ makes mistakes must correct them.
| A．Who | B．That | C．Whoever | D．Whatever |
We must take steps to prevent the __________ world population.
| A．exploded | B．exploding | C．explosion | D．explosively |
The amount of money that he saved reached _________ 30000 dollars.
| A．as many as | B．as much as | C．as high as | D．as far as |
It is pretty well understood_______controls the flow of carbon dioxide in and out of the atmosphere today．
| A．that | B．when | C．what | D．which |
Mary got into acting purely _____________.
| A．accidental | B．accident | C．by accident | D．with accident |