build a fire under someone—(also: light a fire under someone) do smth. to motivate or stimulate a person; make smb. work better or harder:
- These students are incredibly motivated. You don’t have to build a fire under them.
Note:
a) The expression does not correlate in meaning with the phrase throw someone into the frying pan—(U.S.) place smb. with insufficient training into a serious predicament, assuming he will adapt to the situation:
- They threw me into the frying pan. I was off to Japan for the first time in my life and not a soul did I know, and not a word of Japanese.
b) The expression is not equivalent in meaning to the phrase keep someone’s feet to the fire—(also: hold someone’s feet to the fire) pressure a person to undertake smth.:
- We have to continue to keep Kerry’s feet to the fire and remind him of his promises, and continue to keep his feet to the fire on certain issues.
burn someone at the stake—reprimand or scold a person severely:
- Stop yelling. I made a simple mistake, and you’re burning me at the stake for it.
See also: burn someone down / burn someone up.