This activity narrows in on subordinating conjunctions. Combining sentences can be very tricky. I am creating activities that focus in on each skill so they can be taught in isolation. One way to combine sentences is by using subordinating conjunctions. This activity introduces the idea and gives the students hands on practice. First, students sort the sentences by needing a comma or not needing a comma. After that, the students will add the comma where it belongs for the sentences that need a comma.