With so much work , they feel worried all the time.
A. doing
B. to do
C. done
D. having done
网友回答
A. doing
(答案→)B. to do
C. done
D. having done
解析：句意：由于有如此多的工作要做，他们一直感到担心。 with复合结构在句中可以做状语，表原因，伴随状况等。其结构是：with +现在分词/过去分词/介词短语/其他成分。再如，With so much work to do,I can’t go to the movies. 其中with + sth to do 表示有事将要做，由此据题意选B。
考点:考查with复合结构的用法。