| a piece of cake /ə ˌpiːs əv ˈkeɪk/ | very easy | The test was a piece of cake — I finished in ten minutes. |
| break the ice /breɪk ði aɪs/ | make people feel relaxed when they first meet | We played a game to break the ice on the first day of camp. |
| under the weather /ˌʌndə ðə ˈweðə/ | a bit ill | I'm feeling under the weather — I think I've got a cold. |
| once in a blue moon /wʌns ɪn ə ˌbluː ˈmuːn/ | very rarely | My uncle lives in Australia, so we only see him once in a blue moon. |
| cost an arm and a leg /kɒst ən ˌɑːm ənd ə ˈleɡ/ | be very expensive | Those trainers cost an arm and a leg! |
| on the tip of my tongue /ɒn ðə ˌtɪp əv maɪ ˈtʌŋ/ | almost able to remember a word | What's her name? It's on the tip of my tongue. |
| keep an eye on /kiːp ən ˈaɪ ɒn/ | watch something to make sure it is OK | Can you keep an eye on my bag while I buy a drink? |
| make up your mind /meɪk ʌp jɔː ˈmaɪnd/ | decide | Pizza or pasta? Make up your mind — the waiter is waiting! |
| hit the sack /hɪt ðə ˈsæk/ | go to bed | I'm exhausted — I'm going to hit the sack. |
| in the long run /ɪn ðə ˌlɒŋ ˈrʌn/ | after a long time; in the future | Practising every day is hard, but in the long run it pays off. |