a vampire bat的用法和样例：
- A vampire bat.
- A vampire bat came flapping in from the night covered in fresh blood and parked himself on the roof of the cave to get some sleep.
- A vampire bat comes back to his fellow vampires with a bloody mouth. They stare at him jealously and ask him where he got the blood.
- Leon: Why is a vampire locked away here?
- Snape will not be revealed to be a vampire.