I'm trying to describe a scenario where, for a parent, their child has gone long enough (for them) to ______?
- be worried
Honestly, both of them sound ok to me (not a native speaker), apart from the fact that be worried is longer to spell out. And searching on Google Ngram shows that enough to worry is more prevalent, though enough to be worried is also used sometimes.
And I can also think of other situations where the phrase would be used:
- The speed at which species are dying off is fast enough (for us) to ____
- The radioactive wastes are leaking at an alarming rate, enough for us to ____
I'd like to know, is any one of them "wrong"/should be avoided, or is there any difference between these two, mood, emphasis, etc.? Any reason to choose one over the other?