the time at which a situation starts to change in an important way转折点,转机
The organization called the new regulations a turning point in the campaign against smoking.该组织称这些新规定是禁烟运动的转折点。
The turning point in her political career came when she was chosen to run for a Senate seat.她被推选参加竞选参议院议员,这成为她政治生涯的转折点。