化学课上，老师讲到了盐类化合物。
当老师讲到有趣奇异或让你惊讶的事情，继续听下去，点头或微笑示意。
When your teacher says something that sound interesting, curious, or surprising, go ahead and nod or smile.
当老师讲到那些听起来有趣，奇特或令人吃惊的事情，请继续听下去并点头致意或微笑示意。
When your teacher says something that sound interesting, curious, or surprising, go ahead and nod or smile.
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