learn the rule: then / than
- then is an adverb, usually indicating the time at which an event has occurred or will occur, as an addition, or to add emphasis
- I will find your sock, then I will find your potato.
- If you don't give me your potato, then I will be forced to eat your sock.
- I ate your potato and then I ate your sock.
- than is a conjunction & preposition, most commonly in comparisons
- You're more ugly than everyone.
- There's no-one more stupid than you.
- The two are not interchangeable.
- Getting it wrong makes you look stupid. And ugly.