An example of wake up is to get out of bed at 6 a.m.
Wake your brother up, it's time for school.
Some businesses were slow to wake up to the importance of the Internet.
That's the third time you've made the same mistake. Wake up!
An example of wake-up used as an adjective is in the phrase "wake-up call," which is a call to a guest's room at a hotel to get him or her up in the morning.