一个足球运动员在足球场上剧烈运动时，突然发生抽搐现象，这是因为他的血液中可能是下列哪项含量太低引起的
Restaurant
Feature(特征)
Sea House
It is ____but ____
Hometown Restaurant
It has ____
Friends Restaurant
It is ____ but has ____
在“验证机械能守恒定律”的实验中，实验装置如图甲所示．
The car ______ at the present speed until it reaches the foot of the mountain at about nine o'clock tonight.
