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。

《牛津词典》

Some say that gestures on “soft” issues, such as the environment and gay rights, do nothing to move the electorate; the bread-and-butter of public services and incomes is all that counts.

有人说对环保或是同性恋权利等问题采取温和的姿态，并不能感动选民；基本的公众服务和收入问题才是关键。

youdao

The cost of butter quadrupled and bread prices increased by a factor of five.

黄油的价格是原来的4倍，面包的价格上涨了5倍。

《柯林斯英汉双解大词典》

For the bread-and-butter work that many big law firms rely on, haggling has become the norm.

WSJ: Law Firms Raise Rates, but Ease Blow With Discounts

This one isn't as sexy as a big product unveiling, but software is the bread-and-butter of WWDC.

CNN: What to expect from Apple's event today

Idei has now assumed a long-range strategy role, giving day-to-day control to President Ando, the 58-year-old former chief of the bread-and-butter electronics division.

FORBES: Godzilla Needs Batteries