bread and butter什么意思？

The mobile phone business was actually his bread and butter.移动电话业务实际上是他的主业。a piece of bread and butter一块黄油面包Employment and taxation are the bread-and-butter issues of politics.就业和征税是很重要的政治问题。...

bread and butter的音标：bread and butter的英式发音音标为：[bred ænd 'bʌtə]bread and butter的美式发音音标为：[brɛd ənd 'bʌtɚ]...