Matching Pairs LanguageOnline version Idioms by Fernando T. 1 My blood is boiling 2 Butterflies in my stomach 3 Hit the sack 4 It’s raining cats and dogs 5 A couch potato 6 A piece of cake 7 Cost an arm and a leg 8 I am under the weather 9 In hot water Very expensive Something that you say when it is raining heavily Nervous and anxious Very easy! To be in difficulties I am very angry! Go to sleep! A person who doesn’t have an active life I am sick!