用所给动词的适当形式填空。

1. By the time I ______ ( get ) home, Mother ______ ( finish ) cooking.

2. _______ you _______ ( listen )to tapes yet?   No. I _______ (listen) in an hour.

3. You are interested in       (drawing). You might _____ (become) an artist in the future.

4. What ______ your little brother ______( do )? Don't speak so loud. He _______.( sleep )

5. The new teacher who _______ ( teach ) us chemistry ______ just_____ ( walk ) into the classroom.

In each of the following groups of words, there are four underlined letters or letter combinations marked A, B, C and D. Compare the underlined parts and identify the one that is different from the others in pronunciation. Mark your answer by blackening the corresponding letter on the Answer Sheet（）.

A. what  

B. water    

C. walk    

D. talk