in his backyard he built a small garden
The nouns in the sentence are tree and the compound noun backyard.
I have an awning in my backyard.
There is a black cat in the backyard.
The verb in the sentence is are, in the 3rd person plural form of the verb to be
He found genuine gold in our backyard.
there is a wolf like coyote in the backyard.
I watched the birds in my backyard with my binoculars.
You can use a hoe to dig a place for trees in your backyard.
A wren is a bird so a good sentence would be: There is a wren that built a nest in my backyard
injured
The crotchety old man chased the kids out of his backyard.
Spaceship is the subject.