by a single action having immediate effect
一下子，一举
attitudes cannot be changed at one stroke.
态度不可能一下子改变。
do no work at all
什么也不干，根本不工作
precisely at the specified time
准时地，准点地
he arrived on the stroke of two.
他两点准时到达。
disconcert someone so that they do not work or perform as well as they might; break the pattern or rhythm of someone's work
打乱…的工作进度；打扰
a profitable transaction
有利可图的交易，赚钱的交易
an outstandingly brilliant and original idea
非凡的创见
a fortunate occurrence that could not have been predicted or expected
突交好运，突然走运