sign language
noun /ˈsaɪn læŋɡwɪdʒ/
  /ˈsaɪn læŋɡwɪdʒ/
[uncountable, countable]- a system of communicating using hand movements rather than spoken words, as used by people who cannot hear手势语 - They communicate in sign language.他们用手语交流。 
 - Not all deaf people use sign language.并非所有耳聋的人都使用手语。 
- I got by with broken Chinese and sign language.我用蹩脚的汉语加上比比画画勉强应付。 
 
- They communicate in sign language.