天 (tiān) — day; sky

Character

一个星期有七天。 Yí ge xīngqī yǒu qī tiān. A week has seven days.
今天我很忙。 Jīntiān wǒ hěn máng. I'm very busy today.
我明天不上班。 Wǒ míngtiān bú shàngbān. I'm not working tomorrow.
他在北京住了三天。 Tā zài Běijīng zhù le sān tiān. He lived in Beijing for three days.
你一天喝几杯水？ Nǐ yìtiān hē jǐ bēi shuǐ? How many cups of water do you drink a day?
妈妈等了他半天。 Māma děng le tā bàntiān. Mom waited for him half the day.
这个星期有几天不上班？ Zhège xīngqī yǒu jǐ tiān bù shàngbān? How many days this week don't you have to work?
天上有很多飞机。 Tiānshàng yǒu hěn duō fēijī. There are many airplanes in the sky.
你星期天回家吗？ Nǐ xīngqītiān huí jiā ma? Will you go home on Sunday?
一天学一点儿，不难。 Yìtiān xué yìdiǎnr, bù nán. Learn a little each day — it's not hard.