兔子尾巴长不了

1. • rabbits don't have long tails (idiom)
2. • its days are numbered
3. • won't last long

Character by character

• 兔(tù)rabbit
• 子(zi)noun suffix, as in 椅子 yǐzi "chair"
• 尾(wěi)tail
• 巴(ba)Ba, a state during the Zhou dynasty
• 长(cháng)long
• 不(bu)no
• 了(liǎo)finish