2--But what do you think this idiom means? Clam Up
 
1--Hey, how was your weekend?
 
2--It was great. I went to on a nice bike ride and met with friends for dinner. What beautiful weather.
 
1--And... How did your date go Friday with my friend Pat? Well..
 
2--Uh, no, why are you clamming up? C'om, talk.
 
1--I am sure he is great. I just don't think we're right for each other...
 
2--The "calm up" means to say nothing... or stop talking.
 
1--This idiom compares a clam closing its shell to a person shutting his or her mouth.
 
2--We use this expression to describe a person who, for whatever reason, does not want to give a response.
 
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注解：
 
1.Clam Up保持沉默 
2.describe描述
3.response回应

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译文：

1--蛤是一种生活在水里的贝类。
2--你觉得这个习语是什么意思呢？保持沉默
1--嘿，你周末过得怎样?
2--不错。我去骑车了，还和朋友们一起见面吃了个饭。天气很好。
1--那你周五和我朋友帕特的约会怎样？额...
2--噢，不，你为什么不吭声了？说吧。
1--我知道他很好，只是我觉得我们不合适.
2--calm up的意思是什么都不说，或者是停止说话。
1--这个习语是把蛤合上的样子比喻成人合上嘴巴。
2--我们用这种表达方式来描述某人因为某个原因不给出回应。