There’s not much to a smile, when you think about it. At its simplest – in a child’s drawing, say – it’s just a curved line. It doesn’t need lips to frame it, and a nose, eyes and ears are all optional. So when you start looking, you see smiles everywhere – in the grooves of tree bark, in the folds of laundry, even in the metal of a letterbox.

Share the smiles you find in the things you see around you and we’ll feature a selection in the new Happy for Life section.

You can share your photos by clicking on the blue ‘Contribute’ button on this article. You can also use the GuardianWitness smartphone app or the new Guardian app and search for ‘GuardianWitness assignments’.

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