keep-up

(v) maintain a required pace or level
- He could not keep up and dropped out of the race
(v) 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
sustain, prolong,
(v) 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
conserve, maintain, preserve,
(v) keep informed
- He kept up on his country's foreign policies
keep abreast, follow,
(v) 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

sustain prolong conserve maintain preserve keep abreast follow

keep in keep on