1851年是伦敦正式建市的第一年，也是第一届世界博览会的召开之日。

The 1851 is the first year of London as a city, which is the year of the first world fair.

youdao

1851年是伦敦正式建市的第一年，也是第一届世界博览会的召开之日。

The 1851 is the first year of London as a city, which is the year of the first world fair.

youdao