牽馬到河易，強馬飲水難 [牵马－－－－强马饮－难]

Jyutping hin1 maa5 dou3 ho4 ji6 , koeng4 maa5 jam2 seoi2 naan4
Pinyin qiān mǎ dào hé yì , qiǎng mǎ yǐn shuǐ nán

Definitions (CC-CEDICT)
  1. You can lead a horse to water, but you can't make him drink. (idiom)