'keep up' definitions:

Maintain a required pace or level; "He could not keep up and dropped out of the race"

Lengthen or extend in duration or space; "We sustained the diplomatic negotiations as long as possible"; "prolong the treatment of the patient"; "keep up the good work" [syn: prolong, sustain, keep up]

Keep in safety and protect from harm, decay, loss, or destruction; "We preserve these archeological findings"; "The old lady could not keep up the building"; "children must be taught to conserve our national heritage"; "The museum curator conserved the ancient manuscripts" [syn: conserve, preserve, maintain, keep up]

Keep informed; "He kept up on his country's foreign policies" [syn: keep up, keep abreast, follow]

Prevent from going to bed at night; "The anticipation of the trip kept the children up all night"; "I kept myself up all night studying for the exam"