I need a 12 grade level complex/compound sentence using an infinitive and two prepositional phrases.

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Sure! To generate a 12th grade level complex/compound sentence using an infinitive and two prepositional phrases, let's break it down into steps:

1. Begin with an independent clause: "The student excelled in physics."
- This establishes the main idea of the sentence.

2. Add an infinitive phrase: "The student excelled in physics, aiming to understand the universe's deepest mysteries."
- The infinitive phrase "to understand the universe's deepest mysteries" expresses the purpose or goal of the student's excellence in physics.

3. Include the first prepositional phrase: "The student excelled in physics, aiming to understand the universe's deepest mysteries beyond textbooks."
- By adding the prepositional phrase "beyond textbooks," we emphasize that the student's understanding goes beyond what is covered solely in course materials.

4. Introduce the coordinating conjunction: "The student excelled in physics, aiming to understand the universe's deepest mysteries beyond textbooks and through practical experiments."
- The conjunction "and" connects two related ideas and signals a compound sentence structure.

5. Incorporate the second prepositional phrase: "The student excelled in physics, aiming to understand the universe's deepest mysteries beyond textbooks and through practical experiments at renowned laboratories."
- By adding the prepositional phrase "at renowned laboratories," we highlight that the student engages with the subject matter in reputable research settings.

The final complex/compound sentence becomes: "The student excelled in physics, aiming to understand the universe's deepest mysteries beyond textbooks and through practical experiments at renowned laboratories."