In the following sentence,
Ty and Chris care more about Arsene Wenger than they do Arsenal.
What is the proper name for the role of the verb do here in the context of grammar?
For example, the role of they in this sentence is pronoun since it replaces the phrase Ty and Chris to avoid duplication. The same goes for do which replaces the phrase care about, but do is a verb so it is definitely not a pronoun. What is the correct name of it?