Here's why they use "ka":
* Respect: "Ka" (and its male equivalent "krap") is a sign of respect towards the person you're talking to, particularly if they're older or in a position of authority.
* Politeness: It's considered polite and courteous to use "ka" in most everyday conversations.
* Gendered Language: Thai language is highly gendered, with different forms of speech for men and women. "Ka" is specifically used by women, while men use "krap".
It's important to note that using "ka" is not a rule that must be followed 100% of the time. It's more about understanding the social context and using it appropriately. For example:
* You might not need to use "ka" with close friends or family members.
* In informal settings, you might omit "ka" for a more casual tone.
Learning to use "ka" correctly is a great way to show respect and improve your communication in Thai.