Use this checklist as a list of reminders while you are editing your paper.
11. Words easily confused
"Effect" is most often a noun (the effect), and "affect" is almost always a verb.
Other pairs commonly confused: "lead"/"led" and "accept"/"except."
Check a glossary of usage to find the right choice.
The recession had a negative affect on sales.
The recession had a negative effect on sales.
(or) The recession affected sales negatively.
The laboratory instructor chose not to offer detailed advise.
The laboratory instructor chose not to offer detailed advice.