A sentence starts out like...

A sentence starts out like the beginning of a wooden roller coaster. It takes time to load all of the passengers and check for safety, like it takes time to compile the ideas for a sentence and ensure that the content makes sense within the context of the writing. A sentence begins slowly. Roller coasters seem to take forever to reach the top of the first hill. The suspense is often nerve wracking and uncomfortable, just like the beginning of a sentence. By the end of the ride, passengers are excited, and often want to take another ride. Once a writer finishes a good sentence, they are anxious to start their next one. Over time, a writer may even be brave enough to try other roller coaster, maybe less shaky as they work their way to smooth, steel roller coasters.