A dictionary of Confusable Phrases: More Than 10,000 Idioms and Collocations

be mixed up • mix it up
be mixed up —(coll.) be confused in one’s feelings: No won-
der the boy turned criminal, he had been mixed up all through
his childhood.
mix it up —(sl.) argue or exchange criticisms; quarrel vigor-
ously: Shaffer was aggressive and didn’t mind mixing it up
when she had to.
be nettled • be on nettles
be nettled —be vexed or angered: Becker was nettled at the
groan from those around the table. “I know it’s a lot of money,
but this is necessary.”
be on nettles —be impatient or anxious: Some of them were
on nettles till they learned your name was Dickson.
Note: 
Neither expression correlates in meaning with the phrase
grasp the nettle—take decisive or bold action: It was hoped
that, grasping the nettle with resolution, he might suffer no
evil results.
be nobody’s business • like nobody’s business
be nobody’s business —said of smth. that does not concern
anyone: I look like death warmed up and what I feel is no-
body’s business.
like nobody’s business —(coll.) said of an activity done with
great energy or enthusiasm: “He can sing like nobody’s busi-
ness,” said Stoker.
be none of someone’s business • have no business
to do something
be none of someone’s business —said of smth. that does not
concern a person: She’s not his girlfriend, and this matter is
none of his business.
have no business to do smth.—have no right to do smth.:
This woman had no business to publish his private letters to
her.
be of one mind • be single-minded
be of one mind —(of two or more people) be in complete agree-
ment; think alike: Upon sober reflection, I cannot say that I
am of one mind with the pastor.
Note:
The expression is not antonymous in meaning to the
phrase be in two minds—(also: be in twenty minds) feel doubtful
or hesitate about smth.: I am still in two minds whether to take
the house or not.
be single-minded —have but one purpose; concentrate on ac -
complishing only one task: Isabella was single-minded in her
determination to cause Blanche as much trouble as possible.