expression, godan verb (-ku)
be ready to cry; be on the verge of tears
Describes a child or adult whose face is about to crumple into crying, often with a pouting expression.
叱られた子供はべそをかいている。
The scolded child is on the verge of tears.
彼は悔しくてべそをかきそうになった。
He was so frustrated he almost started crying.
The word べそ is a child's word for the face or a pouting expression, and かく here means 'to make (a face)'. The phrase literally means 'to make a crying face'.