IF AN Englishman wants to speak a foreign language, runs the old joke, he can always go abroad and speak English. Over the past decade the number of secondary-school children in Britain passing exams in modern languages has almost halved. Just 30% bother with French, by far the favourite second language (see chart). On March 22nd a House of Lords committee called for compulsory language-learning in primary and secondary schools.

English schoolchildren are not utterly monolingual. Comparatively rapid immigration in the past decade means 15% of children attending schools in England speak a different language at home. In central London more than half do.

This helps flatter the language-learning figures. Polish, Portuguese and Arabic are more popular, although their rise has hardly countered the falls in French and German. Some schools enter children for exams in their native tongue without having taught them in it. This boosts the confidence of a newly arrived child—and the school's ranking in league tables.

Part of the reason for the decline of modern languages is that the rewards of speaking in a second tongue diminish as more people in other countries speak English. Another is simply that learning languages is hard and tends to happen only if schools or the state insist on it. In 2004 the government removed the legal compulsion to teach foreign languages past the age of 14. Just 23% of state schools now ask their pupils to be proficient in a second language at the age of 16, compared with 82% of private schools.