Only in recent years ______ begun to realize that wild dogs, kept within bounds, often do more good than harm.
| A．people have | B．since people have | C．have people | D．people who have |
The old man often looked back on the past days ________ he worked hard to make a living.
| A．which | B．when |
| C．where | D．that |
Recently I have bought an iPad 3 on the website of taobao. com, ________ the price is very reasonable.
| A．on which | B．in which |
| C．of which | D．from which |
Have you ever seen any trees ________ leaves were black because of the polluted air?
| A．whose | B．that |
| C．which | D．who |
The scientist won the Nobel Prize in Chemistry, ________ made him famous all over the world.
| A．this | B．that |
| C．what | D．which |
The result was not the same ________ the professor had expected, ________ was rather disappointing.
| A．as; which | B．which; as |
| C．as; that | D．that; which |