100 Mistakes #19 - Concentrate and Focus

I usually write these blog posts in a quiet café because I need to concentrate. If it's too noisy, I can't focus on what I'm writing. I lose my focus. I lose my concentration.

focus can be a noun or a verb

concentrate is a verb

concentration is a noun

In my classes, I often hear the expression, "I was concentrated". Unfortunately, this is not an English sentence.

Although a person can concentrate, they cannot "be concentrated." We use "concentrated" as an adjective to describe something that has been intensified.

Washing-up liquid is concentrated when its water content has been reduced.

A campaign can be concentrated when an organisation targets a particular area or audience.

But you cannot 'be concentrated' because no one has concentrated you!

Here are some examples:

New Bio concentrated washing-up liquid lasts longer and cleans better! √
The Labour party's campaign was short but extremely concentrated, targetting poorer communities. √
I have been concentrated on this problem all morning. X
I have been concentrating on this problem all morning. √

On the other hand, people can be focussed (and so can a political campaign.)

For example:

She was focussed on winning the tournament. √
The campaign was poorly focussed so voters stayed at home. √

But washing-up liquid cannot be focussed. That's why it's not very good at winning tennis tournaments or elections!


Have you been concentrating?

One of the following statements is incorrect. Which one?

Michael didn't go out because he was concentrating on his exams.
Michael didn't go out because he was focussing on his exams.

Michael didn't go out because he was concentrated on his exams.

Michael didn't go out because he was focussed on his exams.