Don’t treat the vase as if it _______ made of steel.
| A．is | B．was |
| C．were | D．had been |
My father retired in 2008, _____ he has been devoting his time to gardening.
| A．at which | B．since when |
| C．when | D．after that |
During the meeting a young man cried out suddenly and threw his notebook at Ma Yingjiu, ________brought the room to disorder.
| A．this | B．it |
| C．and that | D．and which |
April 23 is stated as World Book Day, an important date for literature around the world, _______ Shakespeare was born and died.
| A．where | B．when |
| C．which | D．what |
We human beings should be very careful with what we do with nature, _____power is beyond our understanding.
| A．that | B．which |
| C．whose | D．where |
（）I found the lecture hard to follow because it ____ when I arrived.
| A．started | B．was starting |
| C．would start | D．had started |