get the measure of somebody

Từ điển Oxford Advanced Learner 8th

get/take/have the ˈmeasure of sb | get/have/take sb's ˈmeasure idiom
(formal)to form an opinion about sb's character or abilities so that you can deal with them
•After only one game, the chess champion had the measure of his young opponent.
Main entry: ↑measure_idiom