Originally Posted by Casiopea

That's just it, M56. Without all the facts, all the options should be provided. Empower your students. If the participle phrase is part of the integral meaning of the main clause, then don't add commas. Otherwise, add commas. Knowing when to add and when not to add requires a sense of what the writer is trying to express. One writer may use commas, and one writer won't use commas. It all depends on expressive style. Bottom line: provide the options. It's descriptively accurate, not to mention empowers the learner.