This thread is for serious learners of English. It's not
for small talk. If you're sure you're a serious learner of
English, write anything. You can, say, copy and paste
passages of English poetry or an English or American novel
you love, or passages of an English movie you're watching,
or something about what you'are doing now to learn English.
You can of course write about some grammatical issues that
passionate you, too. You can write either in English or Japanese.