An idiom is an expression that means something else than its separate words might suggest. Many idioms are peculiar to a specific language. Therefore, you should be careful when you try to translate an idiom from your own language into another.

There is a children’s game called follow the leader. One child is the leader and the others must follow and repeat what that child does.

Follow the leader has become an idiom meaning go along with, do as you are told, obey. In my native Swedish the saying is follow John. When I was young I worked as a farm helper in Wales. The farmer often took me and his family to various markets and fairs, where we could discover the latest in farm machinery, admire award-winning sheep and see fine displays of cakes and flower arrangements. The whole thing meant a lot of criss-crossing over large areas from one spectacle to another, and once when the farmer was hurrying along with the rest of us following in his footsteps,  I shouted, ”Now we’re following John!” I had no idea that the English expression is different, and since the farmer’s first name was John, I thought I was really witty. I always addressed him by Mr. Wrench and never called him John. His family must have thought that I was very impolite. 

A family is walking in the gutter with sleeping mats over their heads to protect them from heavy rain.The image illustrates the idiom 'follow the leader' as a reminder to be careful when you use idioms.
Following the leader

Here are some English idioms with their equivalents in Swedish and some other languages:

Carry coals to Newcastle
To express that you do something that is redundant or completely pointless, you can say in English to carry coals to Newcastle. Since Newcastle is known for its coal, it’s meaningless to carry coals there. The French expression is porter de l’eau à la rivière (carry water to the river), and in Swedish it is gå över ån efter vatten (cross the stream to get water). The German idiom is Eulen nach Athen tragen (carry owls to Athens – the owl is a symbol of wisdom and there were many wise men in old Athens).

Beat around the bush
To say that you avoid doing or talking about something unpleasant or difficult, there is the English idiom beat around the bush. The corresponding Swedish expression is gå som katten kring het gröt (walk like the cat around hot porridge). There is a similar expression in German, um den Brei herumreden (talk around the porridge). In French the saying is tourner autour au pot (going around the pot). The Italians say menare il can per l’aia (lead the dog to the barn).

Foot the bill
If you ask someone to foot the bill, you want them to pay the costs. This is in German zur Kasse bitten (ask someone to come to the cash desk). In Swedish you have to betala kalaset (pay for the party) or stå för fiolerna (pay for the violins).

The straw that broke the camel’s back
This idiom means that something small will be the final action that causes a large and unwanted reaction. The Swedish equivalent is the drop that made the cup run over. Other European languages such as German, French, Italian and Spanish also refer to a cup that runs over.

Out of the frying pan into the fire
This is an expression saying that something is going from bad to worse. The Swedish saying is ur askan i elden (out of the ashes into the fire).

Kill two birds with one stone
This means that you can achieve two goals with just one action. In Swedish we say slå två flugor i en smäll (hit two flies with one swat). Danish and German are other languages that refer to flies instead of birds.

Miss the boat
If you are too slow to take advantage of an opportunity and it’s now too late, you miss the boat. In Swedish we say tåget har gått (the train has left).

Let the cat out of the bag
Inadvertently disclose a secret. The Swedish equivalent is prata bredvid munnen (talk beside your mouth).

Cost an arm and a leg
To say that something is very expensive is in Swedish kosta skjortan (cost the shirt).

IDENTICAL IDIOMS IN ENGLISH AND SWEDISH

Many idioms are almost identical in English and Swedish. The following are some examples.

Cast pearls before swine
Offer something to someone who does not understand it or want to use it

No smoke without fire
A rumour about someone is probably true

Play with fire
Do something risky that may harm you

Hit the nail on the head
Do or say something that is exactly right

Grab the bull by its horns
Directly take strong action to deal with a problem

Sleep like a log
Sleep very deeply without being woken by any noises

Strong as an ox
Be very strong

Like father, like son
Resemble a parent in appearance or behaviour

Sweep things under the carpet
Hide something that is embarrassing or wrong

Put your cards on the table
Be completely honest about your intentions

Eat like a horse
Eat a lot of food

Throw in the towel
Admit that you are defeated

You need to be careful when you use idioms. So, if you talk about a cat walking round hot porridge, a native English speaker will look very surprised.

You will find more English idioms here.