NGS Style Manual‎ > ‎- A -‎ > ‎

as well as

As a preposition this phrase means "in addition to" or "besides" and usually takes a gerund:
            She spends time in the laboratory as well as teaching three classes a week.

As a conjunction, it means "and in addition" or "and not only" and needs parallel construction:
            She teaches as well as researches.

A phrase beginning with "as well as" after a singular subject does not change the singular verb and is often set off by commas:
            John, as well as Jane, is . . . .