Expression﹕Butter
【明報專訊】◆bread and butter
It refers to an activity by which somebody makes a living.
e.g. Please don't fire me! This job is my bread and butter.
◆butter up
It means "to please somebody with a lot of good words".
e.g. Having buttered up his boss, he got promoted.
◆a knife through butter
It means "without obstacles".
e.g. The construction work was finished like a knife through butter.
[Smarties' Power English 第233期]