箭在弦上jiàn zài xián shàng〈比喻fig.〉事情已经到了不得不做或话已经到了不得不说的时候{high time to shoot the arrow already fitted to the bowstring; do sth. that has to be done}: ～,不得不发。{arrow fitted to the bowstring cannot avoid being discharged — one cannot but go ahead; one has reached the point of no return}?