[StavrosK]

Maybe it depends on where you're from? In my Greek head-accent "e" and "a" are very different. Same with "their" and "there" (the-ir, the-r).

When I speak, of course, they sound identical, but my spoken accent is not the accent I think in.

[cycojesus]

I don't think it's a question of sound. (I'm french) 'they're', 'their' and 'there' sound the same (spoken or in my head), but their meaning has nothing in common so I never mistake one for another. How you acquire a language plays here. I learned english fully conscious of what I was doing rather than my organic absorption of french.

[StavrosK]

Oh, of course. I'm just saying that the most common reason for conflation (the fact that they're homophones) doesn't exist for me.