托业考试

试题来源：托业-1
【单选题】 This region ______as the costliest place to do business.
A．(A) often is referred
B．(B) is often referred
C．(C) is referred often to
D．(D) is often referred to

参考答案：D
网考网解析：
Adverbs of indefinite frequency can appear between the auxiliary and the main verb. Choices (A), ... 查看试题解析出处>>