Hi,
First, in the following sentence, is 'adding' a gerund? Yes.
Adding comments (has/have) been disabled for this video.
If yes, is 'comments' part of this gerund also? I think of it as the object of 'adding'.
Second, what should follow 'adding comments'? While 'comments' is a plural, shouldn't 'adding comments' be considered a single activity? Yes, so say 'has'.
If I wanted to write more carefully, I would write this as The function (or method, or ability) to add comments has been disabled for this video.
[ How would you add comments to a video, anyway? ]
Finally, I was wondering whether 'what pumpkins being dropped off a building' takes a plural verb.
i.e., Ever wonder what pumpkins being dropped off a building (look/looks) like?
My guess is 'looks', but it's kind of confusing because without 'being dropped off a building', it takes a plural verb.
The subject of the verb 'look' is the plural 'pumpkins', so say Ever wonder what pumpkins being dropped off a building look like?
On the other hand, you could say Ever wonder what dropping pumpkins off a building looks like?
Best wishes, Clive