1 . I was observing and copying the behaviors of my cat ________ my mom came in, ________ with shock.

A．when; freezing

B．while; frozen

C．when; frozen

D．while; freezing

2 . 过去三年，我们齐心协力、共克时艰，始终相信：路虽远，行则将至。(as)(汉译英)

3 . ______ halfway through our exercise, the teacher changed her mind and collected all our papers.

A．When being

B．When we were

C．Since we were

D．Having been

4 . Everyone in the village regarded him as a genius, ________ he went to college at the age of 14.

A．that

B．for

C．which

D．why

5 . ________ the internet, a blog seized my eyes that human footprints might ________ the ecosystem.

A．When I surfed; sharpen	B．When I was surfing; threaten
C．While surfing; sharpen	D．I surfed; threaten

6 . 他从沙漠中死里逃生后，详细地向朋友们描述了他的经历。(escape) (汉译英)

7 .          , you can turn to me for help.

A．However the problem is difficult	B．No matter how difficult is the problem
C．No matter how is difficult the problem	D．However difficult the problem is

8 . You should put yourself _________ you will be while bathing the baby and make sure that everything is easy to reach.

A．at which

B．in place that

C．where

D．from where

9 . No matter how _________, you can never be sure what the interviewer is going to ask.

A．you are prepared	B．are you prepared
C．prepared are you	D．prepared you are

10 . About 80% of all marine waste is plastic from bottles and packaging. This rubbish runs into rivers _________ it rains and then flows into the sea.

A．since

B．when

C．unless

D．until