10 very commom Idioms and Phrases in English! Idioms are words or phrases that have a cultural context behind them and shouldn't be taken word for word. You have most likely already heard some of these on TV or movies... Learning idioms can take a while, but it comes in handy to know the most common of them. That will make you sound - and feel! - way more confident when speaking to natives! Here they go: - ‘The best of both worlds’ – means one can enjoy two different opportunities at the same time. "Hannah Montana had the best of both worlds: she was a teenage hyper-success as well as an unknown girl leading a normal life" - ‘Speak of the devil’ – the person one is just talking about actually appears at that moment. “Hi Andrew, speak of the devil, I was just telling Sara about your new house.” - ‘Once in a blue moon’ – an event that happens infrequently. “I only go to the beach once in a blue moon.” - ‘When pigs fly’ – something that will never happen. “When pigs fly he’ll decide to move out of his mom's.” - ‘To cost an arm and a leg’– something is very expensive. “Meat these days costs an arm and a leg.” - ‘A piece of cake’– something is very easy. “The Spanish test was a piece of cake.” - ‘To feel under the weather’ – to not feel well. “I’m really feeling under the weather and can't go out with you guys.” - ‘To kill two birds with one stone’ – to solve two problems at once. “I killed two birds with one stone: ” - ‘Call it a day’ – Stop working on something - ‘Let someone off the hook’ – To allow someone, who has been caught, to not be punished. Do you know any very common idioms in English? Let me know! =)