I know the question I'm asking is so specific that you may be reluctant to answer, but I have no other place to find my answer.
I have a sentence, on the Sciencealert site, in which the writer did not use, as my guess, "s" for the verb in the second clause. Why? Is it grammatically correct? How it formed?
The sentence is:
The goal of this study was to search for genetic underpinnings of male sexual orientation, and thus ultimately increase our knowledge of biological mechanisms underlying sexual orientation.
Why the "increase" verb has not s? Is not its subject "the goal"?