Sleep thought" is the sort of thing you get typically before you fall asleep and it's like "did I take the garbage out, ??

半睡半醒的想法是指那些,你睡着前所想到的东西,例如“我倒垃圾了吗？

耶鲁公开课 - 心理学导论课程节选

You will likely fall asleep faster because your mind will get tired much like counting sheep at night in order to fall asleep.

FORBES: Mental Exercises to Help Improve Your Memory

Leave it alone long enough, however, and it'll get tired, start snoring and eventually just fall asleep.

ENGADGET: Furby gets a reboot for 2012, we go hands-on (video)

From the time I roll out of the cot at 6 a.m. to the time I fall asleep after midnight, I get to do what I love nonstop.

CNN: Why I sleep soundly in my cot