ถ้า

[thâa ther wâang ná]

If you're free (situation: making plans)

Imperative form used for asking about availability

[thâa yâak gin aa-hǎan Thai]

If you want to eat Thai food (situation: making a suggestion)

Common phrase for expressing desire

[thâa fon dtòk ná]

If it rains, (situation: discussing weather)

Common usage for conditional statements