Surprise idioms work well in Part 2 stories about gifts, news or unexpected meetings. One at the moment of surprise ("out of the blue") and one for your reaction ("I was lost for words") is plenty.
The labels tell you how each one lands with a listener. Natural idioms are safe in any Speaking part. Informal ones suit relaxed Part 1 and Part 2 answers. Overused ones are correct but examiners hear them constantly, so use them once at most. Avoid means dated, slang or a cliché that sounds memorised. None of these belong in Writing Task 2.
12 idioms
unexpectedly
An old school friend called me out of the blue last week.
Very natural and common.
a complete and sudden surprise, often unwelcome
His resignation came as a bolt from the blue.
Natural, stronger than "out of the blue".
surprise someone who is not prepared
The examiner's question caught me off guard.
Natural.
shock or upset someone badly (British)
The news of the factory closing knocked the whole town for six.
British, from cricket. Natural.
I was extremely surprised
My jaw dropped when I saw the price.
Natural and vivid.
was amazed by what I saw
I couldn't believe my eyes when I saw snow in April.
Natural for stories.
so surprised or moved that you cannot speak
When they gave me the award, I was lost for words.
Natural and polite.
a surprising, usually pleasant event (British)
My brother cooking dinner? That's a turn-up for the books.
British and humorous.
surprise someone with something difficult
The interviewer threw me a curveball about my weaknesses.
Natural, originally American.
impress someone greatly
The view from the top blew me away.
Casual and enthusiastic.
appear suddenly and unexpectedly
A cyclist came out of nowhere and I had to brake.
Natural.
I was extremely surprised
When she said she was moving to Peru, you could have knocked me down with a feather.
Long and old-fashioned. It sounds learned for the test.
Part 2
Here is a sample answer we wrote to show how a few of these idioms fit into natural speech. Notice that it uses only a handful, spread out, with plain English around them.
Last year my older brother called me out of the blue and asked me to keep the evening of my birthday free. I assumed it was dinner, but when I walked into the restaurant, about twenty of my school friends were waiting, some of whom I hadn't seen in years. My jaw dropped, and for a moment I was completely lost for words. He'd spent weeks tracking everyone down online.
"Out of the blue" just means unexpectedly and can be positive or negative. "A bolt from the blue" is a noun and describes a sudden shock, often bad news.
Not usually. Long, old-fashioned idioms sound memorised, especially if delivered slowly. "I was lost for words" is shorter and more natural.
No. Idioms belong in Speaking. Writing Task 2 is a formal essay, so idioms and contractions make it sound too casual. Use precise, neutral vocabulary there instead.
One or two, only where they fit what you want to say. Forced idioms sound memorised and can lower your score. On this page, be careful with "you could have knocked me down with a feather": examiners hear them often or they sound dated.
Keep going
More idiom themes:
Practise them on real questions:
Written by Fizza Butool Zaidi and Ali Zaidi. Lexical Resource is one of the four Speaking criteria in the public IELTS scoring guide on ielts.org. BandLadder is not affiliated with IELTS, the British Council or IDP, and no list of idioms guarantees a band score.
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