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What curtain should match with my blue sofa and white wall?
First of all, that is a very beautiful coordination. I guess white
or orange will look good. You can check out online to find another colour to
pair with these. This link may help you: https://www.homedit.com/colors-to-pair-with-blue/. At my
place, the wall is white, the sofas are brown and my curtains are fuchsia.
I believe you mean "cordinate" and not "match". Red would cordinate and look patriotic.
Use a cool colour in the spring/summer, like pastel pink or lemon. Then use a stronger colour in the autumn/winter, such as red or navy blue .