If we are not recycling all our plastic waste, largely because many councils cannot deal with all the variations (Just a third of plastic is recycled, survey shows, 22 November), why are the major supermarkets allowed to keep inventing new wrappings consisting of mixed materials and marked “Not currently recyclable”?

Jean Wood

Hythe, Kent

• In 1970, it wasn’t the work, it was the prospect of sex, drugs and rock’n’roll and escaping from home that was the lure (Our friends from the north, G2, 22 November). Now I crave to return to Liverpool, but London-born husband refuses to go somewhere that’s wetter and colder.

Jennifer Henley

London

• Lewis Carroll’s expression “jam tomorrow and jam yesterday – but never jam today” (Letters, 22 November) is a pun on Latin grammar regarding the usage of iam (then) – which can be used for future or past events, but not in the present tense, when nunc (now) should be used.

Andy Smith

Kingston upon Thames

• Please don’t refer to rich people as “ultra-high-net-worth individuals” (Report, 23 November). These people are of no more or less worth than anyone else, they just have more money.

Mark Walford

London

• Re Crimea, is it “the first time Europe’s borders have been changed by force since 1945” (Donald and Vladimir, G2, 21 November)? What about Yugoslavia?

Myra Gartshore

Dumbarton

• I beg to differ (Letters, 22 November). The humanities encourage me to think that the universe revolves around us. The sciences remind me that it doesn’t.

David William Evans

Leeds

• Was your long read on Danish culture (The hygge conspiracy, 22 November) actually written by Charlotte Hyggens?

Derrick Cameron

Stoke-on-Trent

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