Question

_______ is often the case, we have worked out the production plan.?

A．Which	B．When?
C．What	D．As?

Answer 1

D?

此题考查as位于句首引导定语从句的用法。as 可引导非限制性定语从句，指代其前面或后面的整个句子，而which只能指代前句，不能用于句首。