As more and more cars are produced and used, so the _____ from their exhaust-pipes contains an even larger volume of poisonous gas.
| A．exposure | B．distribution | C．expansion | D．emission |
We should think carefully about ________ Mr. Needham said at the meeting.
| A．that | B．what | C．which | D．X |
Jack was soon told ________ he did was not necessary.
| A．why | B．that | C．how | D．why what |
The energy is ________ makes the cells able to do their work.
| A．that | B．which | C．what | D．such |
It is well known _________ a person eats causes changes in the body.
| A．that what | B．that | C．what | D．how |
________leaves the room last ought to turn off the lights.
| A．Anyone | B．The person | C．Whoever | D．Who |