use or exercise the mind or one's power of reason in order to make inferences, decisions, or arrive at a solution or judgments

devote (oneself) fully to

cause one's (or someone else's) thoughts or attention to return from a reverie or digression

focus one's attention on a certain state

examine closely; focus one's attention on

listen and pay attention

a nation in northern North America; the French were the first Europeans to settle in mainland Canada

a monarchy in northwestern Europe occupying most of the British Isles; divided into England and Scotland and Wales and Northern Ireland; `Great Britain' is often used loosely to refer to the United Kingdom

hold (someone's attention)