wait for the cat to jump 观望形势然后行动，看风使舵，随机应变

【例句】
Cautions politicians always wait for the cat to jump before agreeing with any proposal.
谨慎的政治家在对任何提议表示赞同之前总是要先观望形势。

There is nothing for it but to wait for the cat to jump.
眼前只有静静等待，看看形势如何转变。