厚此薄彼的英文

favor one to the neglect of the other
play favoritism

2007-03-16 10:08:07 補充：
make fish of one and flesh of anotherfrom http://www.cycnet.com/cms/2004/englishcorner/translation/200610/t20061018_429440.htm

Bias is much appropriate then the above suggestions..

Favors one and discriminate against the other

Treat with partiality

Favors one and discriminate against the other

這句中文點解