A well-placed idiom can do wonders for a piece of writing. They add lightness of touch, pack loads of meaning, and make the writing flow.

But a well-placed idiom is no walk in the park, no piece of cake, and no child’s play (= not easy).

For a start, you have to be sure your idiom means what you think it means, and that your audience understands it the same way. In a recent multi-national meeting, our host spoke of ‘grabbing the dragon by the tail’. The two most senior participants nodded, wisely. Everyone else exchanged confused looks: is it good to grab a dragon by the tail, or dangerous? Was this encouragement to be bold, or a warning?

We never did work it out  – but worse, our confusion meant we missed a lot of useful content.

Grammar is another hazard when using idioms. To hit the spot, an idiom has to be grammatically correct, otherwise it can stick out like a sore thumb (= look wrong), and that native-English feeling you want to achieve falls flat on its face (= fails). So ‘fake it till you make it’ really needs those pronouns; ‘fake till you make’ doesn’t work.

Our advice? With regret, it’s this: avoid using idioms in academic writing. It’s just too easy for them to be misunderstood. Ask yourself ‘what do I want to say?’ Then say it, in simple terms that can’t be misinterpreted.

That way you will avoid the kind of mistake a close friend made. He is fluent in five languages, and has won awards for his research. Lately he told me, with great pride, that his latest piece of work looks ‘like a dog’s breakfast’. I was shocked. ‘A dog’s breakfast’ means something is a real mess, and needs a lot of work. So I asked him what he meant.

“A dog’s breakfast!” he said, with a big smile. “A dog is really happy to get its breakfast – does that not mean it’s the best thing ever?”

Top tip: don’t use idioms!