So I'm trying to make a sentence which goes, "My effort is still not enough", and I came up with
I was thinking about using wa, however since "足りない" is intransitive, I wondered if I should use ga instead?
If you say「私の努力」it follows that you would use は.
By saying 「私の努力」rather than just「努力」, the sentence already begins by singling the speaker out, so I think は would most naturally follow.
If you drop the「私の」you could naturally use は or が depending on the context.
Your boss comes over to your desk to discuss a project that your team has been working on:
Your project failed again, eh Bobby?
Yeah, I'm just not putting in enough effort. (*Maybe if I tried something other than just putting in effort, things might have worked out differently...)
Yeah, not enough effort is being put in. (*A lack of effort is the problem. Maybe it's me, maybe it's the team...)
Yeah, not enough effort is being put in. (*Lack of effort is a problem, maybe there are other problems too...)