Complete the plural as in the example:

1.One balloon four balloons
2.One tree two.......
3.One cat two.......
4.One frog three........
5.One bird two.........
6.One star tree........
7.One book two...........
8.One cow two...........
9.One chair two.............
10.One rabbit three...........
11.One doll two.........
12.One ball four ball​