with his business, Mr.Green seldom had a talk with his family face to face.

A．Occupying

B．Occupied

C．Being occupied

D．To be occupied

目前环境污染在世界范围内很大部分的原因是对能源的利用引起的，这主要是( )

A．化石资源利用

B．煤炭资源利用

C．电磁能利用

D．核裂变能利用