The teacher's intolerance of tardiness was justifiable.

Yes, it's OK.

Hi,

Is this sentence natural? Not to me, unless you want to be formal to the point of sounding stiff and artificial.

The teacher's intolerance of tardiness was justifiable.

I suggest The teacher was right not to put up with lateness.



Clive

Tom, when you are asking if sentences are natural, it might help to mention the context -- particularly, whether you mean in conversation or in written English. This sentence, for example, is pretty unlikely in conversation, but is fine (to me, anyway) in crafted written English, which is how I assumed you were intending to use it.