non-speaker          
noun [ C ] (also nonspeaker) uk/ˌnɒnˈspiː.kər/ us/ˌnɑːnˈspiː.kɚ/
 不说某种语言的人
someone who does not speak a particular language
  Subtitles are provided for non-speakers of German.
 She rarely used Gaelic, except very occasionally to keep a secret from her son or some other nonspeaker. 她很少使用盖尔语,除非偶尔需要对她儿子或其他不会说盖尔语的人保密。 
  不(能)说话的人
a person who does not speak or is not able to speak
  We want to improve the communication skills of non-speakers.
 Some help is available for severely impaired nonspeakers. 严重残疾不能说话的人可以获得一些帮助。 
 - More examples
 - One report raised concerns about teaching native speakers and non-speakers together.
 - It is difficult for a non-speaker of Russian to evaluate these errors.
 - An intensive one-year English course is available for nonspeakers.
 - There are many communication constraints with which nonspeakers have to struggle.
 
Idiom   
be (on) non-speakersidiom  UK informal(因有争执而)不说话 
If two people are non-speakers or are on non-speakers, they do not talk to each other because they have had an argument.
  This usually inseparable pair now appear to be non-speakers.
 She is still on non-speakers with me because of what I wrote in my last article. 因为我在上一篇文章中写的内容,她仍然不和我说话。