The children were delighted when the jack in the box popped out.
Дети были в восторге, когда чёртик в коробочке выскочил.
Definitions
A jack in the box is a children's toy that consists of a box with a lid that, when opened, causes a figure (often a clown or jester) to spring out unexpectedly. The phrase can also refer to a situation or person that is unpredictable or surprising.
