Welcome to the first of my weekly mini-posts on troublesome pairs of words.  Keep on suggesting new pairs on the comments to my original post!

So, today it’s affect and effect.

Quite a simple one – if you AFFECT something, it means you have an EFFECT on it.

Well, not quite that simple …

Affect is (mainly) a verb, which means “to have an effect on”, or to “make a difference to.”  Effect is used mainly as a noun, the difference that is created when something is affected.  It’s an end result or consequence.

Although you can also “Effect a change in something”, this is a different verb used in a different way.  And an affect is also used in other senses, such as to denote pretending or as a precise term in psychology, but we won’t worry too much about those uses, as they’re not the ones that tend to get mixed up.

Examples:

Bill’s injury affected his ability to play in the team, and had a bad effect on the team’s morale.

Bill affected the morale of the team when he got injured.  The effect was to make them play less well.

I will affect the balance of this blog between grammar and opinions when I post all these mini-posts.

When used in combination with another drug, this drug can affect the side-effects in a positive way.

The effect of the water on the runner was marvellous; he perked up immediately.

Sarah effected a change in the way the meetings were structured.

Thanks as usual to the Concise Oxford English Dictionary and New Hart’s Rules for helping back me up!