Example sentences
nǐ你zài在jiā家ma吗？
Are you home?
tā他zài在gōng工zuò作。
He's working.
The story behind the character
在
才 on top, 土 (earth) below. A plant just breaking through the soil. That's existence. Xu Shen wrote 在, 存也: "to exist." So "我在家" is literally "I exist, here at home."