Cytat:
1) When the same verb is required before and after than/ as, we can use an auxiliary after the second verb:
I learn less than he does.
2) When the second clause consists only of than/as + I/we/you + verb, and there is no change of tense, it is usually possible to omit the verb:
I'm not as old as you (are).
He has more time than I/we (have).
In formal English we keep I/we, as the pronoun is still considered to be the subject of the verb, even though the verb has been omitted. In informal English, however, me/us is more usual:
He has more time than me.
They are richer than us.
3) When than/as is followed by he/she/it + verb, we normally keep the verb: You are stronger than he is.
But we can drop the verb and use he/she/they in very formal English or him/her/them in very colloquial English.
I swim better than he does/ than him.