Britain (or Great Britain) and the United Kingdom (or the UK) include England, Scotland, Wales and Northern Ireland. (Sometimes Britain or Great Britain is used just for the island which includes England,
Scotland and Wales, without Northern Ireland.)
The British Isles is the name for England, Scotland, Wales, the whole of Ireland, and all the islands round about.
Note that England is only one part of Britain. Scotland and Wales are not in England, and Scottish and Welsh people do not like to be called 'English'.

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THE gRlTtSH ISLES
Fact
There are roughly 6,500 spoken languages in the world today. However, about 2,000 of those languages have fewer than 1,000 speakers. The most widely spoken language in the world is Mandarin Chinese. There are 885,000,000 people in China that speak that language.
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