—Must I turn off the gas after cooking?
—Of course, you can never be ____careful with that．
| A．enough | B．very | C．so | D．Too |
15. As Polly was riding on the train, she sensed that she was _____ by a tall man in a dark coat.
| A．being stared | B．being watched | C．being attached | D．glanced |
14. Over the long process of evolution, animals have developed their ______ senses, which makes it possible for them to _____ their environments.
| A．specially; conquer | B．unique; survive |
| C．uniquely; survive | D．special; exist |
13. His ability is beyond question; _____ has been in doubt is ____ he is prepared to work hard
| A．what; that | B．which; whether | C．what; whether | D．that; that |
12. Half of the students will have sports, and the rest _____ to be here in the classroom studying.
| A．is | B．was | C．were | D．are |
11. She dedicates herself to her work. She is such a dedicated teacher that her efforts will _____.
| A．pay off | B．be fed on | C．pay back | D．be given back |