Sitting in the atrium, Marcus chatted pleasantly with a pretty student from his chemistry class, but then he had to leave suddenly, because he noticed that he had only thirty seconds to get to Professor Spottke's English class on time.

Question

Should you remove the comma after atrium?

Or should you remove the comma after suddenly?

Answer 1

The comma after "atrium" should be removed. The phrase "Sitting in the atrium" is an introductory participial phrase that leads directly into the main clause without needing a comma. The sentence would then read:

"Sitting in the atrium Marcus chatted pleasantly with a pretty student from his chemistry class, but then he had to leave suddenly, because he noticed that he had only thirty seconds to get to Professor Spottke's English class on time."

The comma after "suddenly" is appropriate, as it separates the independent clause that follows.