兩手準備 have plan B

兩手準備英文有好多種講法(看下), 但我始終覺得 plan B 容易記和貼切.

e.g. I suggest you guys should have plan B if this.....does not work!

(同義詞)

have a contingency plan
have another string to one's/your bow
prepare oneself for both eventualities