I'm glad you made that mistake for it will serve as a warning to you.A. In caseB. In a

问题补充：

, Im glad you made that mistake, for it will serve as a warning to you.

A. In case

B. In a way

C. In return

D. In relief

答案：

A. In case

(答案→)B. In a way

C. In return

D. In relief

解析：短语辨析。A以防：B在某种程度上；C作为回报；D鲜明，显著；句意：在某种程度上，我很高兴你犯了那个错误，因为我可以给你警告。故B正确。