1) Unresolved grievances could adversely affect the motivation of employees (affect = before or during a process - how something will change something else) 2) Unresolved grievances could have an adverse effect on the motivation of employees (effect - the end result = what happened after the changes were made) How will it affect you?(before it happens} How did it affect you?{after it has happened} What was the effect it had on you?{after it has happened} Notice the different structures in the last two sentences. They have the same meaning.

Neither sentence is correct. The correct sentence is: Unresolved grievances could adversely affect THE motivation of employees. {They AFFECT it.} [This sentence implies emotional impact.] [Something emotional] AFFECTS [something else.] For example: Pain affects work. AFFECT (VERB) - implies emotion or sensory feeling. AFFECTION = a warm positive feeling. EFFECT (NOUN) - an act that is independent of emotion or sensory feeling. EFFECTIVE = something that works successfully. The EFFECT of the accident was that she was unable to work properly because pain AFFECTS work. Her work was AFFECTED by pain. If she has a mean boss then she may be fired, EFFECTIVE immediately. https://en.wikipedia.org/wiki/Afferent_nerve_fiber#/media/File:Afferent_(PSF).png Here is another way to remember the difference. An AFFERENT nerve carries sensation to the brain. The brain FEELS. An ERRENT nerve carries motor impulse from the brain. The muscles WORK.

Hello, (affect) is a verb (effect) is a noun So, you can use both but with some changes. Using (affect)... Unresolved grievances could adversely affect the motivation of employees Using (effect) Unresolved grievances could have an adverse effect on the motivation of employees Hope that was of any help