keep up

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 negociations as long as possible”
• “prolong the treatment of the patient”
• “keep up the good work”

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”

keep informed

• “He kept up on his country”

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”