keep somebody on their toes

keep (one) on (one's) toes

To force someone to stay active, alert, and focused on something or someone. Having two kids under age five sure keeps me on my toes!
See also: keep, on, toe

keep somebody on their ˈtoes

(informal) make sure that somebody is ready to deal with anything that might happen by doing things that they are not expecting: Regular surprise visits help to keep the staff on their toes.This job really keeps me on my toes.
See also: keep, on, somebody, toe