cannot have one thing to serve two purposes 魚與熊掌不可兼得

cannot have one thing to serve two purposes
繁：魚與熊掌不可兼得
简：鱼与熊掌不可兼得

行政長官梁振英指發展土地和保留郊野公園用地兩者存在矛盾，是「魚與熊掌，不可兼得」。

梁振英：發展土地與郊野公園難兼得（2015年11月10日）。now 新聞，取自 http://news.now.com/home/local/player?newsId=157432

“Land is like other resources. Sometimes we cannot have one thing to serve two purposes,” he said.

Turn parks into housing: Areas with ‘low ecological value’ could be used for new flats, CY says. (2015, November 10). South China Morning Post. Retrieved from http://www.scmp.com/news/hong-kong/economy/article/1877363/country-park-areas-low-ecological-value-could-be-used-housing