get in sb.'s hair

1. 惹煩某人
   The children kept getting in my hair.

   孩子們不停地惹惱我。

harm a hair of sb.'s head

1. 損某人一根毫毛
   If you harm a hair of my daughter's head, you'll get yourself into trouble.

   你要是動我女兒一根毫毛，你可就自找麻煩了。

let one's hair down

1. 不拘禮節
   It's wonderful to let your hair down at the weekend after you've been working hard all week.

   辛苦工作一週後在週末不拘禮節輕鬆一下真是太好了。

make sb.'s hair stand on end

1. 令某人毛骨悚然
   It would make your hair stand on end.

   那會使你毛骨悚然的。

not turn a hair

1. 不動聲色
   Susan just stood and didn't turn a hair.

   蘇珊站著不動聲色。

split hairs

1. 作極細微的分析
   Scholars nowadays just split hairs; they never address the basics.

   當今的學者只做不必要的細微區分；他們從來不談根本。

   David loves to split hairs.

   大衛就愛作一些瑣細的分析。

• hair of the dog
  informal an alcoholic drink taken to cure a hangover. [from hair of the dog that bit you, formerly recommended as an effective remedy for the bite of a mad dog.]
• a hair's breadth
  a very small margin.
• in (or out of) someone's hair
  informal annoying (or ceasing to annoy) someone.
• keep your hair on!
  Brit. informal stay calm.
• let one's hair down
  informal behave uninhibitedly.
• make someone's hair stand on end
  alarm someone.
• not turn a hair
  remain apparently unmoved.
• split hairs
  make overfine distinctions.