Both Days
noun
Kanji doesn't go together much better than this. Both plus day equals both days. This is a bit of a formal word though, you'll hear important people say it more than your friends.
りょうじつ
This is a jukugo word, which usually means on'yomi readings from the kanji. Since 日 has two on'yomi readings, here's a mnemonic to help you remember which one to use: On both days of your vacation, you get two boats to row! Gee, two (りょうじつ) boats at once? Try not to fall in!
両日のスケジュールをメールして下さい。
Please email the schedule for both days.
両日とも雨になるそうですよ。
It looks like it'll rain on both days.
ごめんなさい。両日とも、ミーティングが入っています。
Sorry. There are meetings on both days.