Busy
noun, な adjective
If you've had many busy days, then you're even more busy than you thought!
This is a jukugo word that uses the on'yomi readings of the kanji. You should be able to read this on your own.
ここ最近、多忙で全然ワニカニのレビューができてません。
Lately, I've been so busy that I haven't been able to do any reviews on WaniKani at all.
彼は多忙な生活を送っています。
He leads a busy life.
男が「多忙」で会えないって言うのはウソだよ。多忙でも時間は作れるもん。会えない理由は「金がない」か「気持ちがない」かのどっちかだよ。
When a guy says he's "too busy" to meet up, it's usually a lie. Even if he's busy, he can make time. The real reasons for not meeting are either "a lack of money" or "a lack of interest."