keep up at
phr. v..phr. v.. to continue doing something difficult or to stay at a high level of performance.
phr. v.. to maintain a consistent pace, effort, or standard in a specific activity; often implies persistence in the face of fatigue or difficulty.
You are doing great work, so please keep up at it.
If you keep up at your piano practice every day, you will see huge improvements by summer.
Despite the grueling schedule and the lack of immediate results, the researchers decided to keep up at their experiments until they found a breakthrough.
usually followed by 'it' or a specific activity; implies a steady, ongoing effort.
contrast with 'keep up with' (matching someone else's speed); 'keep up at' focuses on the speaker's own persistence in a task.
He keeps up at to run.He keeps up at running.the preposition 'at' must be followed by a noun or a gerund (-ing form), not an infinitive.