Sitting duck

Example

Competitors are in disarray, they look like sitting duck

Water off a duck's back

Example

These unnecessary criticisms is like water off a duck's back

Lame duck

Example

We cannot expect a lot from a lame duck parliament

Take to like a duck to water - on the fly

Example

He's taken to his new difficult job like a duck to water

To walk the dog

Example

I usually walk the dog early in the morning before going to work

Let sleeping dogs lie - don't rock the boat

Example

Shall I ask Kevin if he's upset at my coming late in the mornings? If I were you I wouldn't do it, just let sleeping dogs lie

Every dog has its day

Example

He'll find the right job eventually, every dog has its day

It's raining cats and dogs

Example

 Here it's been raining cats and dogs, and the forecast says it won't let up until Monday

To lead a dog's life

Example

You should live wisely and work twice so that you don't end up having to lead a dog's life

To be the underdog

Example

In the final of the Champions League Apoel Nicosia is the underdog with Bayern München

To fight like cats and dogs

Example

My parents fight like cats and dogs

Lie down with dogs, wake up with fleas

Example

Going around with George worsened his attitude, lie down with dogs, wake up with fleas

Barking dog never bites

Example

Take it easy, he is just a blabbermouth, barking dog never bites

To have other fish to fry

Example

Come back later now I have other fish to fry

Exploitative fishing

Example

The reckless use of the sea demands a dramatic reduction of exploitative fishing