If you don't want to sound impolite, or cause embarrassment or distress of any kind to the person you're talking to, you should learn to use tactful and tentative forms in your English.
如果你不想听起来不礼貌，或对与你谈话的人造成任何形式的尴尬或窘迫，你应该学会在你的英语中使用委婉试探性的话语。
You should make good use of your spare time to practice English.
你应该充分利用空余时间操练英语。
Please use English to define a particular thing you are familiar with. You should include functions and examples apart from class and characteristics of it in the definition.
请使用英语来定义一个特定的事情你都熟悉。你应该包括函数和例子除了在定义类和特征。
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