知恵がつく
知恵のある
知恵を貸す
give advice [【形式ばった表現】 counsel] 《to》
think hard 《about a difficult problem》
知恵をつける
give somebody a hint [suggestion]; put an idea into somebody's head
match [pit one's] wits against somebody
try and see who is the cleverest
(a) teething fever
one's brain.