筑巢

The nesting instinct is proper to birds.

是鸟类本能。

The swallows are nesting in the woodshed.

燕子正在小棚呢。

The swallows are building a nest under the roof of our house.

燕子正在屋檐下。

Some birds build nests of twigs.

一些鸟用枝。

Summer migrants nest here.

夏天候鸟来这。