过硬

过硬	guò yìng	to have perfect mastery of sth / to be up to the mark
过	Guō	surname Guo
过	guò	to cross / to go over / to pass (time) / to celebrate (a holiday) / to live / to get along / excessively / too-
过	guo	(experienced action marker)
硬	yìng	hard; stiff; solid / (fig.) strong; firm / resolutely; uncompromisingly / laboriously; with great difficulty / good (quality); able (person) / (of food) filling; substantial