unsuitable       
adjective uk/ʌnˈsuː.tə.bəl/ /ʌnˈsjuː.tə.bəl/ us/ʌnˈsuː.t̬ə.bəl/
B2 不适宜的;不合适的
not acceptable or right for someone or something; not suitable
  The software blocks material that is unsuitable for children. 这个软件会屏蔽不适宜儿童的内容。 
 Synonyms: improper (WRONG) inappropriateirregular (RULE) unacceptableunbecoming
 - More examples
 - They officially designated the area as unsuitable for human habitation.
 - Completely unsuitable candidates were screened out at the first interview.
 - The programme's subject matter was quite unsuitable for children.
 - Time after time she gets herself involved in relationships with unsuitable men.
 - We were intending to walk up Ben Nevis but she had no coat and was wearing totally unsuitable footwear.