To build a harmonious society, we must ________ low-paid citizens and poor population．

1. A.
   turn to
2. B.
   get down to
3. C.
   devote to
4. D.
   pay attention to

_____to his research work,the professor cared little about any other things.

A.Devoting                                 B.Devoted

C.Having devoted                 D.To devote

_____to his research work,the professor cared little about any other things.

A.Devoting                                 B.Devoted

C.Having devoted                 D.To devote

        to his scientific research, the professor cared little about his family.

_____to his research work, the professor cared little about any other things．