The birds are similar in appearance ,but the male ____ more

The birds are similar in appearance ,but the male ____ more ____ are the birds doing?The birds are sing in the tree.选Whe ( )the male are more beautiful than the female in the world These two new cameras are quite similar in appearance,but th Why are male birds usually more beautiful than female birds? are the birds in the The twin sisters are similar ___ each other ___ appearance b Two cats are ____ the tree.There are some birds in the tree. same similar the are they but not 怎么组合 There are many fish in the area,and the birds can catch ____ there are many birds in the forest .birds with there are many birds in the sky