give off发出，放出；
give off通常表示“发出（光、气味、声音等）”，后接的宾语一般位于off之后。
What we give off is what we get back.
我们散发的.能量就是吸取到的能量。
China will give off much less poisonous gases into the air.
到那时中国向大气释放的有毒气体将大大少于过去。
Cars give off much poisonous gas every day.
汽车每天释放出很多有害气体。
