使劲

使劲	shǐ jìn	to exert all one's strength
使	shǐ	to make / to cause / to enable / to use / to employ / to send / to instruct sb to do sth / envoy / messenger
劲	jìn	strength / energy / enthusiasm / spirit / mood / expression / interest / CL:把 / Taiwan pr. [jing4]
劲	jìng	stalwart / sturdy / strong / powerful