焦油加工的主要任务是获得酚、萘、蒽等纯产品和（）等粗产品。
参考答案：洗油沥青
They usually get there a little _____ than we _____. [ ]
A. earlier; did
B. earlier; do
C. earlier; get
D. more early; do
1/2,1/3,1/6,1/18,1/108,( )
A．1/216
B．1/324
C．1/1080
D．1/1944
