Excuse me, how to tell children how to write the word "left"

From the perspective of "writing", the first two are naturally better. Because children don't know how to write "seasoning" at all, it's useless to say it (not to mention the first two).

But to master and remember this word, you have to tell the meaning and form several words.

So I suggest telling him how to write according to the first two paragraphs, and then explaining the word "seasoning" for him to remember.