Barking dogs seldom bite.

吠犬不咬人。

Every dog has his day.

凡人皆有得意日。

Dog does not eat dog.

同类不相残；同室不操戈。

a cat-and-dog life

争争吵吵的日子

Give a dog a bad name and hang him.

人言可畏。

go to the dogs

每况愈下 ；堕落

hang-dog look

愁眉苦脸

Love me, love my dog.

爱屋及乌。

He is a lucky dog.

他是个幸运儿。

lead a dog's life

过着猪狗不如生活

not have a dog's chance

毫无机会

top dog

当权派；头儿

a lazy dog

懒汉

a dirty dog

下流坯

as/like a dog with two tails

高兴得跟什么似的

be (old) dog at

对…有经验；对…很内行

Beware of a silent dog and still water.

提防不吠的狗,小心静止的水。

come like a dog at a whistle

一呼即来

It is ill to waken sleeping dogs.

别惹事生非。/别惹麻烦。

Hungry dogs will eat dirty puddings.

急不暇择, 饥不择食。

dog it

拈轻怕重，逃避工作

put on the dog

装模作样；装出斯文、有钱或有文化的样子

a dog in the manger

占马槽的狗；占着茅坑不拉屎的人

help a lame¹ dog over a stile

助人于危难之中；雪中送炭

He who has mind to beat his dog will easily find a stick.

欲加之罪，何患无辞。