鱼与熊掌

yú yǔ xióng zhǎngyuyuxiongzhang

1. lit. the fish and the bear's paw, you can't have both at the same time (idiom, from Mencius); fig. you must choose one or the other
2. you can't always get everything you want
3. you can't have your cake and eat it

Study it in Yanamino