2. to write- เขียน Always a useful verb. When communicating in a foreign country, having something in writing is always a tremendous help. If you don't remember how to say it (whatever it happens t0 be) or can't say it correctly, have someone write it down. An address, something you're looking for at the grocery store, a person's name, a menu item; all of these things can be written by someone you might find that speaks your language enough to communicate with them in it. They can then help you to communicate with others. Knowing a few simple terms, you can as people to write something down in your target language. Very useful.
One nice thing about Thai: like Chinese, they don't conjugate their verbs, so the dictionary form for "to write" is just "write" whether I'm doing it or you are or they are or even if we were doing it yesterday or you will have done it tomorrow (although these other cases can sometimes add things to the verb, it's not necessarily conjugation in the true sense, and most of those time and tense clues are given by other words in the sentence like 'yesterday', 'before' 'tomorrow' 'later' and so on). This makes it very convenient to learn a word and know that you'll pretty much use it just like that across the board, or at least can and still be understood.