Where no comma is needed, write "none."
1. After reading the report that you gave me yesterday I changed by mind but according to the original memordanum it's too late for me to do anything about it.
2. Because her alarm clock was broken she was late for class.
3. Having finished the test he left the room.
4. He ran out the door where he paused to kiss his mother.
5. However the suspect owns a purple clown wig.
6. I like to run early on Tuesdays.
7. I like to run early when it is still cool.
8. If you are ill you ought to see a doctor.
9. It was snowing in Nome despite the weatherman’s promise of sun.
10. Likewise the angry mob beat the mascot and pelted him with mud.
11. Nonetheless we would prefer lima beans
12. On Sunday you'd better come early.
13. She was late for class because her alarm clock was broken.
14. Students who are ineligible for scholarships can still apply for these special bursaries but they will have to wait until September to do so.
15. The candidate promised to lower taxes protect the environment reduce crime and end unemployment.
16. The Constitution establishes the legislative executive and judicial branches of government.
17. The prosecutor argued that the defendant who was at the scene of the crime who had a strong revenge motive and who had access to the murder weapon was guilty of homicide.
18. We went to the show though we would have preferred to remain home.
19. When the snow stops falling we'll shovel the driveway.
20. While I was eating the cat scratched at the door.
Examples adapted from the Purdue University Online Writing Lab & Ian Johnston of Malaspina University-College, Nanaimo, BC.