Here's a breakdown:
* Introductory Phrase/Clause: This sets the stage or provides context for the main idea of the sentence. It can be a prepositional phrase, participial phrase, infinitive phrase, or an adverbial clause.
* Main Clause: This contains the subject and verb of the sentence and expresses the main idea.
Examples:
* After the long, tiring hike, we finally reached the summit. (Introductory prepositional phrase followed by main clause)
* Running towards the finish line, she tripped and fell. (Introductory participial phrase followed by main clause)
* To get a good grade, you must study hard. (Introductory infinitive phrase followed by main clause)
* Because it was raining, we decided to stay inside. (Introductory adverbial clause followed by main clause)
Key points to remember:
* Introductory phrases/clauses should be followed by a comma if they are more than four words long or if they are essential to the meaning of the sentence.
* The main clause should make sense on its own, even without the introductory phrase/clause.
* The introductory phrase/clause and the main clause should work together to form a complete thought.