needn't       
uk/ˈniː.dənt/ us/ˈniː.dənt/
 不需要
short form of need not
  You needn't come until later. 你不必现在就来。 
 - More examples
 - You needn't do the washing up.
 - We needn't take coats with us.
 - Tom needn't come if he doesn't want to.
 - Diabetes needn't mean you can't enjoy your food.
 - We needn't tidy up until tomorrow.