一个表示状态，一个表示动作。
wake up：英 [weik ʌp] 美 [wek ʌp] 醒来；活跃起来；引起注意；（使）认识到
举例：
A cool shower wakes up the body and boosts circulation.
冷水澡可以刺激身体，促进血液循环。
I nearly always wake up fresh and rested.
我几乎每天醒来都精神抖擞，得到了充分休息。
You have to wake up now, baby.
该起床了，宝贝儿。
She set the alarm so she'd wake up in time to give her two sons theirmedication.
她定了闹钟，以便及时醒来给两个儿子服药。
get up：英 [ɡet ʌp] 美 [ɡɛt ʌp] 站起来；（使）起床；安排；举起
举例：
I got up and walked over to where he was.
我起身走到他那边。
They have to get up early in the morning.
他们大清早就得起床。
They knew how to get themselves up in those days.
那时候，他们懂得打扮。
He's much better and can get up now.
他好多了，能下床了。