By all means的意思是“一定”、“无论如何”、“用一切手段”.例：
You must bring him here by all means．
你们一定要设法把他带到这里来.
This project must be realized by all means．
这个规划必须要实现.
You should by all means warn him before he leaves for Singapore．
你务必在他去新加坡之前提醒他.
By all means亦可用于回答,表示有礼貌的同意,作“好的”、“当然可以”解.例：
May I have one?—Yes,by all means．
我可以拿一个吗?——当然可以.
