We were all laughing up our sleeves at the teacher when he was up at the blackboard explaining the math problem. He had a rip in the back of his pants and didn't know it.
这句话翻成中文就是：“当老师在黑板前讲解数学题的时候，我们都偷偷地笑，因为他裤子后面有个裂缝，他自己还不知道。”
We were all laughing up our sleeves at the teacher when he was up at the blackboard explaining the math problem. He had a rip in the back of his pants and didn't know it.
当老师站在黑板前解释数学问题的时候我们都在暗暗笑他，他裤子后面有一条裂缝而他不知道。
We were laughing in our sleeves at the teacher when he was up at the blackboard explaining the math problem. He had a rip in the back of his pants.
当老师在黑板前讲解数学题的时候，我们都偷偷地笑，因为他裤子后面有个裂缝。
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