1、A gravitational field or an electric field, you can't.
在重力場或者電場里面，就做不到了。

2、From Euler equation to Einstein gravitational field equation
從歐拉方程到愛因斯坦引力場方程(英文)

3、The gravitational field is so strong that the escape velocity near it exceeds the speed of light.
重力場是如此的強(qiáng)大以致于靠近它的逃逸速度超過光速。

gravitational field翻譯