Q-Eng

a dog in the manger(まぐさ桶)
someone who keeps something that they do not really want in order to prevent anyone else from having it ：Stop being such a dog in the manger and let your sister ride your bike if you're not using it.

a dog's breakfast/dinner (British & Australian informal)
something that has been done very badly
She tried to cut her hair and made a real dog's breakfast of it.
You should have seen the ceiling after he'd finished painting it. It was a complete dog's breakfast.

a shaggy(毛むくじゃらの) dog story
a joke which is a long story with a silly end
My grandad insists on telling these shaggy dog stories, which nobody finds funny except him.

as sick as a dog
very ill
She was as sick as a dog after eating the stew.

go to the dogs
if a country or an organization is going to the dogs, it is becoming less successful than it was in the past (usually in continuous tenses)
They sat in the bar the night before the election, moaning that the country was going to the dogs.

not have a dog's chance (informal)
to not have any chance of doing something that you want to do (usually + of + doing sth)
He hasn't a dog's chance of getting that job.

If you lie down with dogs, you will get up with fleas.
Prov. If you associate with bad people, you will acquire their faults.
Granddaughter: It's not fair. I'm starting to get a bad reputation just because I'm friends with Suzy and she has a bad reputation.
Grandmother: It's only natural. People think that if you lie down with dogs, you will get up with fleas.

It's a dog's life.
something that you say which means that life is hard and unpleasant
I've got to go to the supermarket, then cook a meal, then pick Dave up from the station - it's a dog's life!

Let sleeping dogs lie.
Prov. Do not instigate trouble.; Leave something alone if it might cause trouble.
Jill: Should I ask the boss if he's upset at my coming in late in the mornings? Jane: If he hasn't said anything about it, just let sleeping dogs lie.
I thought I would ask Jill if she wanted me to pay her back right away, but then I decided to let sleeping dogs lie.

meaner than a junkyard(廃品置き場) dog (with fourteen sucking(乳離れしていない) pups)
Rur. cruel; eager to fight.
Don't mess with her. She's meaner than a junkyard dog with fourteen sucking pups.
They say Jim's meaner than a junkyard dog, but really, he's a sweetheart.

put on the dog and put on the ritz(豪華)
to make things extra special or dress formally for a special event.
Frank's really putting on the dog for the big party Friday night.
They really put on the ritz for us.

shouldn't happen to a dog
Fig. an expression of something that is so bad that no creature deserves it.
Poor guy. That shouldn't happen to a dog.
This cold I got shouldn't happen to a dog.

tail wagging(（尾などを）振る) the dog
a situation where a small part is controlling the whole of something.
John was just hired yesterday, and today he's bossing everyone around. It's a case of the tail wagging the dog.
Why is this small matter taking so much time? Now it's the tail wagging the dog!

the dog days
the hottest days of the summer
Usage notes: Some people believe there is a star called the dog star which can only be seen during a hot period in the summer.
(usually + of ) At times, during the dog days of summer, the stream dries up completely.

There's life in the old dog yet. (humorous)
something that you say which means that although someone is old, they still have enough energy to do things
I may be 90 but there's life in the old dog yet.

throw someone to the dogs
Fig. to abandon someone to enemies or evil.
He served(仕えた) the evil empire well, but in the end, they threw him to the dogs.
discard someone as worthless:　young people look(み) upon(なす) the older person as someone to be thrown to the dogs

the top dog (informal)
the most important and powerful person in a group Jackson was top dog and he made sure he got what he wanted.

Why keep a dog and bark yourself?
Prov. You should not do something you have hired someone else to do.
Ellen: The cleaning lady washes my floors every Tuesday, but I always wash them over again. Jane: Don't be silly, Ellen. Why keep a dog and bark yourself?

work like a dog / trojan(トロイア人)
to work very hard
He worked like a dog all day to finish the wallpapering.

You can't teach an old dog new tricks.
something that you say which means it is difficult to make someone change the way they do something when they have been doing it the same way for a long time You're never going to teach your father at the age of 79 to use a computer. You can't teach an old dog new tricks, you know.


出典
http://idioms.thefreedictionary.com/dog

Lang-8にも書きました。
http://lang-8.com/43673/journals/364155410167776851709162...