General:
* A long time ago
* A brand new start
* A little bit more
* A piece of cake
Figurative:
* A shot in the dark
* A taste of freedom
* A ray of hope
* A drop in the bucket
Specific:
* A happy birthday to you
* A cup of coffee, please
* A walk in the park
* A moment of silence
Humorous:
* A bad hair day
* A dog ate my homework
* A total disaster
* A complete and utter mess