誰知世界第1,2,4長的河流是甚麼?quick is online !!!!!!!!(5點)

It is difficult to measure the length of a river, the more precise the measurement, the longer the river will seem. Also, it is difficult to determine where a river begins or ends, as very often, upstream rivers are formed by seasonal streams, swamps, or changing lakes.

These are average measurements.

1. Nile (6,690 km)
2. Amazon (6,400 km)
3. Mississippi-Missouri (6,270 km)
4. Yangtze (Chang Jiang) (6,245 km)

For a longer list see http://en.wikipedia.org/wiki/Longest_rivers. This also gives more information on measuring river lengths.

第一:尼羅河
第二:亞馬遜河
第4:密西西比州