Suggested Answers for Check Questions

Substitution: if a constituent can be replaced with another constituent they belong to the same constituent-type. E.g. pronouns are DPs and whatever pronouns can substitute will also be DPs in the structure.

Coordination: only identical constituents (with the same function) can be coordinated.

Movement: only constituents can undergo movement. E.g. the sentence *The boy was seen with blue eyes by Mary is ungrammatical as the boy is not an independent constituent in this sentence.