It's common for people to feel physical symptoms of nervousness--rapidly beating heart, quick breathing and shaky hands--before giving a speech.  That's a perfectly normal response caused by a release of adrenaline in the body--something that happens when we feel threatened.  The key is to engage in physical activity to help move the adrenaline through your system and allow it to dissipate.  Clench and release.  Ball up your fists really, really tight and hold for a second or two and then release.  Repeat this a few times.  You can do the same thing by squeezing the muscles in your calves very tightly and then releasing.  With each release, you should feel a reduction in your adrenaline-induced symptoms. Take deep breaths.  The adrenaline in your system causes you to take more shallow breaths that, in turn, increase your feeling of anxiety.  You need to break the cycle. Take a deep breath through your nose and allow the air to fill your belly.  Once your belly is full, let your breath fill and expand your ribcage.  Finally, allow your breath to move fully into your chest.  Open your mouth slightly and begin to exhale starting first with the air in your chest, then the air in your ribcage and finally the breath in your belly.  Repeat this inhale-exhale cycle five times. While it might seem difficult to believe, a good speech is really not about you, the speaker.  It's about the audience.  Plan to put your total focus and concentration on your audience throughout your speech, especially in the beginning.  Really take them in and check out the non-verbal messages they're sending you--do they understand what you're saying?  do you need to slow down?  are they in agreement with you?  would they be open to you moving closer to make a stronger connection?  If you put your attention fully on your audience, you won't have time to think about your own nerves or anxiety. You're probably planning to use visual aids anyway, but if you're not, you might want to consider it.  For some people, using visual aids reduces their...

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Write a summary of the previous text in Vietnamese:
Vận động. Tập trung vào khán giả. Sử dụng dụng cụ trực quan. Tập tưởng tượng. Luôn lạc quan.