Jenny hopes that Mr. Smith will suggest a good way to have her written English _____ in a short period. [ ]

A. improved

B. improving

C. to improve

D. improve

脱硫装置开车时进行凝结水洗的目的是（）。

A、清洗出系统中的泥沙杂质

B、清洗出系统中的焊渣

C、置换工业水，调节系统的PH值

D、对系统进行预膜