Add a sentence to the following sentence highlighting the importance of the action.
He opened the door.
He opened the door, allowing fresh air to circulate and brighten up the room.
Complete the following task based on the instruction and optional input provided.### Instruction:
Add a sentence to the following sentence highlighting the importance of the action.

### Input:
He opened the door.

### Output:
He opened the door, allowing fresh air to circulate and brighten up the room.