Об­ра­зуй­те от слова SCIENCE од­но­ко­рен­ное слово так, чтобы оно грам­ма­ти­че­ски и лек­си­че­ски со­от­вет­ство­ва­ло со­дер­жа­нию тек­ста.

The main routes connect Europe and Africa, Europe and South-⁠Eastern Asia and Australia, North and South America. How do we know about these routes? ______ study birds. They catch birds, place small bands with numbers on the birds’ legs and then let the birds fly away. Some of these banded birds are caught again. The band tells about the route.