世界是由七大洲和四大洋组成。

The world is made up seven continents and four oceans.

这本书是对七大洲的完美介绍。

This book is the perfect introduction to the seven continents.

世界是由七大洲和四大洋组成的。

The world is made up of seven continents and four oceans.

接下来你会看到：全国218个地区，8362个旅游目的地及全世界七大洲12561个旅游目的地的2万多条旅游攻略。

Then you will see more than 20 thousand travel guides which covers 8362 destinations from 218 regions all over the country as well as 12561 destinations from 7 continents.