K-5:keep somebody at arm's length 疏远
A:I have a feeling that Lucy is not so close to Jim as she used to be.
A:我觉得露西对吉姆不像以前那么亲近了。
B:Yeah, when she heard about his background, she decided that she'd better keep him at arm's length.
B：是啊，她听说他的背景后，就决定疏远他了。
A:But Jim feels miserable.
A：可吉姆却觉得很痛苦。
