The most important one is: focus on one speech topic. If you have to come up with a very brief 30~60 seconds or a somewhat longer—two or three minutes--self-introduction, make sharp choices. Do not expect it to be an award winning boring autobiography (自传).Due to the fact you have to speak your speech around one theme, I recommend to develop one aspect of your life. That aspect will tell who you are and what you are about.
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