1 . It is a wise father ________ knows his child.

A．that

B．which

C．what

D．whom

2 . It was with the selfless help of our teacher ______ we realized our dream.

A．that	B．who
C．when	D．how

3 . It was President Xi Jinping ________ visited the navy troops and urged to strengthen naval force on April 9,2013.

A．when	B．which
C．that	D．he

4 . It was in the lab _____ was taken charge by Professor Wang ______ they did the experiment.

A．where, that

B．that, which

C．that, where

D．which, that

5 . Was it because of the heavy snowstorm in Europe ________ the flight had to be put off？

A．which

B．so

C．why

D．that

6 . Mr. Smith didn’t understand _____ made his son so upset that evening.

A．what was it

B．why it was this

C．how that was

D．what it was that