if it kills me
无论多难；无论如何
 
I'll make this marriage work if it kills me. 
无论如何我都要使这桩婚姻幸福。
 
it won't kill you
对你算不了什么；没什么大不了的
 
It wouldn't kill you to stay another half-hour. 
你再待上半小时也没有什么大不了的。
 
kill yourself
自杀；拼老命；竭尽全力
 
He killed himself after suffering from depression for many years. 
他患抑郁症多年后自杀了。
 
kill oneself laughing
笑死人；笑得前仰后合
 
We were killing ourselves laughing when we saw what John was wearing. 
看到约翰的穿着时我们都笑死了。