Tom’s brother who is now a doctor always encourages        hard and go to college.

A．for him studying

B．him studying

C．for him to study

D．him to study

防腐层大修施工时、应分段开挖，分段防腐，上一段完工（）后再开挖下一段。

A.回填

B.填压密实

C.恢复地貌

D.输油