1- I do think that nonhumans can communicate. In the article Vocal responsiveness in male wild chimpanzees: implications for the evolution of language the author explores how chimpanzees communicate by learning symbols. I think that we often think of a language as something that is spoken but there are other ways to communicate with other species. According to the observations of Arcadi chimpanzees can communicate vocally but it is at a low rate only when it needs to be done.
2- Intelligence is the ability to acquire and apply knowledge that is acquired. An example would be a student who takes extensive notes in a difficult class and studies and is apple to apply the material that they learn. For example a law student has to be able to apply all information learned in their classes to pass the Bar Exam and use that knowledge as they practice law.