crunch/ kr^ntʃ /

1.vt.
(with teeth) 嘎吱嘎吱地咬嚼

2.vt.
(underfoot) 使发出刺耳的碎裂声

3.vi.[gravel] [ wheels+] 
发出嘎吱声

4.noun [c] 
(sound) 嘎吱声

5.noun
the crunch (moment of truth) 关键时刻

if/when it comes to the crunch
如果/当必须得做点什么的时候