Don't count your chickens before they're hatched.

鸡蛋未孵出，先别数小鸡。（不要过早乐观。）

Don't count your chickens before they'rehatched.The lesson here: wait until something you want has really happened before assuming it will.

鸡还没孵好先别忙着数。这句教的是：不要在你所期待的事情发生之前，就假设它已成事实。