The villagers in some rural areas mainly __________ on wells for water, without being able to use running water.
| A．rely |
| B．reply |
| C．delay |
| D．apply |
We’retalkingaboutthepianoandthepianist_____wereintheconcertweattendedyesterday.
| A．which | B．whom | C．who | D．that |
Thefreezingpointisthetemperature__________waterchangesintoice.
| A．atwhich | B．when | C．inwhich | D．ofwhich |
Don’t talk about such things _______ you are not sure about.
| A．which | B．that | C．as | D．what |
Hurry! The train _______. You know it _____at 8:30am. .
| A．leaves; leaves | B．is leaving; leaves |
| C．leaves; leaving | D．is leaving; is leaving |
With the help of high technology, more and more substances _________ in the past years.
| A．discovered | B．have discovered |
| C．had been discovered | D．have been discovered |