Gravics
重力场学, 引力场理论
🗣️ 情景例句
I don't think we should see each other any more.
我觉得以后咱们还是别再见面了。
Have but few frieds,though many acquaintances.
结交可以多，朋友应宜少。
Before? After? said the doctor.
“饭前？饭后？”医生说。