keep awake
Examples
Gee, its lonesome in the outfield. It's hard to keep awake with nothing to do.
A man feels impelled to do something to keep awake.
Friendship and domestic happiness are continually praised; yet how little is there of either in the world, because it requires more cultivation of mind to keep awake affection, even in our own hearts, than the common run of people suppose.
I wake up thinking: What am I reading? What will I read next? I'm terrified that I'll run out, that I will read through all I want to, and be forced to learn wildflowers at last, to keep awake.