Question:
The bird perched on the limb and it bent.

it
Answer:
the limb
Question:
The teacher did not recommend William because he was not a good student.

he
Answer:
William
Question:
The master rewarded the dog because he was a good companion.

he
Answer:
the dog
Question:
The environmentalists were angry at the corporation because they had ignored their proposal.

they
Answer:

the corporation