N4 — outside your level filter
probably + write
tabun kaku
probably; I think — the speaker's best guess, offered with room to be wrong
meaning: probably write
今日はたぶん残業するから、先に食べてて。
kyou wa tabun zangyousuru kara, saki ni tabetete.
I'll probably work late today, so start eating without me. casual
あの店、日曜はたぶん休みだよ。
ano mise, nichiyou wa tabun yasumi da yo.
That shop is probably closed on Sundays. casual