(figuratively) to take the plunge; to go for it

(transitive) to bring to heel, to bring into line, to rein in, to make (someone) conform

(figuratively) to run out of steam, to lose one's momentum, to slow down, to languish, to mark time

(informal, figuratively) to take the plunge

tell me about it

(figuratively) to make the first move

(informal, derogatory) not to overstrain oneself, not to over-exert oneself, not to overdo it, not to wear oneself out, not to kill oneself over (something), to take it easy

(informal) and then some! and how!

(informal) to behave in a haughty, insolent, impudent, cheeky, cocky manner; to have some gall, nerve, cheek, etc.

(informal) on the double, at a run