title_body: Structure only conlang? Nouns? Are there examples of conlangs that are used by applying their structure such as grammar, sentence structure, intonation, means of combining words, etc… with other features of a given language or given member of a class of languages?
  
  This has the disadvantage that for understanding one would have to know both the language in question, call this X, and the language it's adapting, call this Y.
  
  For example and in particular I'm thinking that X could use the alphabet and all the single morpheme nouns and verbs of Y, but replace every other aspect of the language with its own.
  
  A possible advantage could be in allowing the speaker more reachable access to an unfamiliar linguistic environment, be that a conlang or a natural language, where different modes of thought are the most natural.
upvoted_answer: It happens with sign languages - often there are two "versions" of a sign language, the first one (less official, natural) is generally used by the community and has its own grammar, the second one (more official, heavily constructed) parallels grammar (syntax) of the corresponding spoken language.
  
  E.g.there is the natural Polish Sign Language, and a rather artificial constructed Signed Polish, following closely the syntax of spoken Polish, so somewhat the opposite of the question, a natural language imposing its grammar over the conlang. But it could be said that the signing system (obviously) imposes its own "phonology" over the spoken language.