Singular or plural after Subject + modal + base form of the verb

For example:

A well thought-out system streamlines operation, improves work process, reduces data redundancy.....

If can is added to the sentence, should the following verb be singular or plural?

A well thought-out system can streamline operation, improve work process, reduce data redundancy.....

or

A well thought-out system can streamline operation, improves work process, reduces data redundancy.....

Solution 1:

The verb "can" is modifying all three verbs, not just the first one (all three verb-object pairs are predicates of "can"). Therefore, all three verbs are in their infinitive form, and do not inflect for the 3rd person singular. No "-s" ending is required.

This is not about singular vs. plural conjugation, it is about infinitive vs. finite verb forms.