Free fall
例子
The rock fell in free fall, picking up speed as it dropped.
岩石以自由落体方式下落,下落时速度加快。
The astronaut felt weightless during free fall in space.
宇航员在太空自由落体期间感到失重。
02
自由落体, 急剧下降
a sudden sharp decrease in some quantity
03
自由落体
the ideal falling motion of something subject only to a gravitational field



























