发生心跳骤停，必须在多长时间内重建循环和呼吸
A. 4-6分钟
B. 2-3分钟
C. 11-12分钟
D. 6-7分钟
As soon as the hostess picks up her napkin, you should ____.
It is impolite to ____ with food in your mouth.
You should wait for your food to cool off, but not ____ if it is too hot to eat. No ____ while you are eating.
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