why do we yawn BBC ENGLISH

0 6 词汇卡 nataliakalista

问题		答案
breathe in and out with our mouth stretched open 开始学习		yawn
can be spread from one person to another 开始学习		contagious
an action, often automatic, in response to a particular situation 开始学习		a behaviour
to feel close to and have a sense of belonging to a group 开始学习		to identify with a group
do, show 开始学习		exhibit
satisfied about something 开始学习		smug