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- They couldn't keep a straight face. 他们没法不笑出来。
- It was difficult to keep a straight face when he fell over the dog. 当他绊着狗摔了一跤时，大家很难扳着脸不笑。
- Judges love to keep a straight face. 法官喜欢保持一张正直的脸。
- I struggled to keep a straight face. 我竭力装出一副一本正经的样子。
- She put pink and green stripes in her hair and looked rather like a Neapolitan ice cream. I couldn't keep a straight face when she asked me what I thought about it. 她在头发上扎着粉红夹绿色的布条，看上去就像夹层花色冰砖当她问我象什么时，我禁不住笑了出来。
- He has such a strange voice that it's difficult to keep a straight face when he's talking. 他的声音很古怪，说起话来很难让人不笑。
- Tom kept a straight face while telling the joke. 汤姆说这一笑话时，丝毫不露声色。
- He kept a straight face and remained speechless. 他绷着脸不说话。
- He always keeps a straight face. 他总是不苟言笑。
- The sight that met my eyes made it hard to keep a straight face. 映入眼帘的情景使我难以板起面孔。
- He sounded so foolish that I could hardly keep a straight face. 他说话听起来那样傻气，我简直忍不住笑。
- It's hard to keep a straight face when someone tells a funny joke. 别人讲笑话时,很难板着脸不笑。
- How Henry managed to keep a straight face, I'll never know. 亨利怎么能一本正经地板着面孔,我永远也不会明白。
- Nonsense! How can you say that and keep a straight face? 胡说八道!你怎能不动声色说那些话呢?
- Vicki: Today's new expression_r is keep a straight face. 我是陈鹂。在今天的节目中，我们要学的是什么呢？
- The story was so funny that it was impossible to keep a straight face. 故事是那么有趣，真叫人忍不住笑。
- It was hard to keep a straight face while I answered their questions. 回答他们的问题时，真叫我忍俊不禁。
- Frank kept a straight face when Kate made a ridiculous mistake. 当凯德犯了可笑的错误时，富兰克忍住不笑出来。
- John looked so comical up there on the stage that no one could keep a straight face. 约翰在舞台上滑稽极了，谁看了谁笑。
- When Bob fell into the water, he looked funny and I could hardly keep a straight face. 鲍布掉入水中时,看起来很滑稽,我几乎禁不住笑出来。
