Nǐ yīnɡɡāi qù lǐfà le.
你应该去理发了。
It's about time you had your hair cut.
Notes:
你(nǐ): you
应该(yīnɡɡāi): should
去(qù): to go
理发(lǐfà): have hair cut
了(le): particle word
Example:
A:你应该去理发了。
Nǐ yīnɡɡāi qù lǐfà le.
It's about time you had your hair cut.
B:好的。
Hǎode.
Sure.