I brought my whistle with me in case of an emergency. Am I being overly cautious?
When are you going to blow the whistle? I can't believe you resorted to that!
I'm going to blow the whistle if I'm going to feel upset.
It's good to have a whistle for emergencies. Blowing a whistle can get the attention of others so they can help you.
I'm going to blow it just for fun.
For fun at random times? That seems crazy, please don't. If you really have an emergency and blow it then people won't believe you after this stunt.