What verbs do you like to add to your games that are not part of the standard set, but are generic enough to be added to most games?
For example, I think TIME(?) and DIAGNOSE were part of many of the Infocom games, but not are not part of standard inform.
“about” and “credits” are fairly common … “help” and “hint” should probably have a response as well, even if your game doesn’t have any built in hints (better to say so than not to recognise the verbs).
“xyzzy” is a pretty common Easter egg (and sometimes “plugh”).
“follow” might be appropriate to some games (eg. after an NPC leaves a room).
By default, “look through” is a synonym for “search” for Inform games; if you have a window, remember to allow the player to look through it.
“swim in/across” and “dive into” might be appropriate if there is a body of water to swim in.
“kick” and “bite” are fairly common, as well as “knock” for doors.
“mend” or “fix” or “repair” might be an obvious action if the game includes a broken object.
“talk to” is good if you have any NPCs (even if it just says to use “ask/tell” instead). “hi/hello/greet”, “bye/goodbye” and “thanks/thank you” can also be appropriate.
If you have any objects with obvious uses, remember to include those as well (eg. “vacuum floor” if there is a vacuum cleaner).
“pet/pat” is pretty common if you have an animal that can be petted/patted.
“remember” is a pretty common action as well if it seems the PC knows more than the player, but it might not apply to your game.
And depending on your tastes, you might want to include the generic verb “use”.
I added several verbs that I think I’d want in most games:
help
trade
drive (vehicles are a built in type, but drive is not recognized?)
talk to
look up (in a book)