The students are ________ the teacher．

1. A.
   listen
2. B.
   listen to
3. C.
   listening
4. D.
   listening to

 The students are ________ the teacher.

       A. listen         B. listen to        C. listening        D. listening to

All the students are listening ________ their teacher.

1. A.
   for
2. B.
   /
3. C.
   in
4. D.
   to

The students are ________ the teacher.

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The students are ________ their teacher.

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