Где нужно поставить the, а где не нужно?

Do you know the Wilsons? They’re a very friendly family.The writer visited ______ Canada and the USA.Kilimanjaro is the highest mountain in ____ Africa.____London is on the Thames._____ Europe is smaller than ______ Africa. The Pacific (Тихий) Ocean is the biggest ocean in the world.London is famous for the Houses of Parliament, ____ Westminster Abbey, The Tower Bridge, the British Museum and the Tower of London.Have you ever been to the Kremlin? My pen friend lives in ______ Trumpington Street, in _____Cambridge. It was the first visit to the United Kingdom.