1.It took Zheng He 28 years to lead 7 ocean journeys in total.

2.He used compasses,ocean maps and other things to help him find new places.

3.He went on his ocean journey with over 200 ships and about 27000 people each time.

4.On ihs journeys,the biggest ship was about 151.8 meters long and 61.6 meters wide.

He visited more than 30 countries and areas.

6.He made the ocean journeys in order to develop trade and friendship between China and other countries.