All the Chinese workers do ________ they can  ______through the hard time.

A．what; get

B．that; to get

C．all what; get

D．what; to get

双向打印机的特点是

A．左右双向同时打印

B．可以选择从左到右打印，也可以选择从右到左打印

C．先从左到右打印，再从右到左打印

D．具有两个打印头