air：
n. 空氣；大氣；天空；空間；微風；樣子；神態(tài)；氣氛
v. 晾；通風；廣播
There was not a breath in the air.
一絲風也沒有。To fish in the air
海底撈月a nip in the air
空氣中有一種刺膚的寒冷
sky：
n. 天，天空
The sky is clearing.
天正明朗起來。Sky is louring.
天空正變得陰沉。After the storm the sky cleared.
暴風雨過后，天空明朗了。
empty：
adj. 空的，空洞的，空虛的
v. 倒空，把…騰出，撤離
n. 空物
The bookshop was empty.
書店里沒有人。The river empties into the ocean .
這條河流入海洋。He that is full of himself is empty
自滿者無知