Sentences can begin with adverbials for several reasons, primarily related to emphasis and clarity.
1. **Emphasis on the Action or Circumstance:** Starting with an adverbial allows the writer or speaker to emphasize the context or the manner in which the action takes place. For example, in the sentence 'Suddenly, it started to rain.', the adverbial 'Suddenly' prioritizes the unexpected nature of the event.
2. **Setting the Scene:** Adverbials can provide important context right at the beginning. In 'In the morning, we will leave for Paris.', the phrase 'In the morning' sets the time frame for the action, preparing the reader for when the events take place.
3. **Improving Flow and Engagement:** Beginning with an adverbial can enhance the rhythm of the sentence or paragraph, making the writing more engaging. This structure can keep the reader hooked by introducing interesting details first.
4. **Variety and Style:** Using adverbials at the beginning can add variety to sentence structure. Varying sentence openings can help maintain reader interest and avoid repetitive patterns.
Overall, beginning a sentence with an adverbial is a stylistic choice that can enhance emphasis, provide context, and improve the overall flow of writing.