1) Wales, Scotland and England are Great Britain.
2) The United Kingdom includes four countries: Wales, Scotland, England and Northern Ireland.
3) The capital of the U.K. is London. (речь о Соединенном Королевстве, а не об Украине)
4) Cardiff is capital of Wales.
5) The Scotland capital is Edinburgh.
6) Belfast is the capital of Ireland.
7) London is the capital of England.