mouth the words

verb2

1. •
   To mouth words in the sense "to make the actions of speech, without producing sound."

   • Indeed, on Dick Clark's madly popular teen-age TV show the various acts never sing at all, but merely mouth the words to their own taped recordings. — 1960
2. •
   To speak insincerely.

   • They mouth the words “democracy” and “Americanism”, but they inject in their preachments national hatred, national aggrandizement, and glorification of the fascist dictatorships. — 1935