Clean the surface first, or the paint will not adhere.

In this sentence i want to use so istead of or. Am i right? Please also explain the use of or in this sentence if it is correct.

  • 2
    It's understood as "If you don't clean the surface first, the paint will not adhere." "So" would only be possible in "Clean the surface first so the paint will adhere".
    – BillJ
    Commented Feb 26 at 8:04

3 Answers 3


'Or' has many uses. In this context, it means 'if not', or 'otherwise'.

This is an imperative with a warning - in other words, you should clean the surface; if you do not then the paint will not adhere.

Changing it to 'so' as you suggest would completely reverse the meaning.

  • 1
    I accidentally typed 'if' instead of 'or' in my first edit and someone downvoted an otherwise correct answer. That's the kind of place this is.
    – Astralbee
    Commented Feb 26 at 11:10

Changing "or" to "so" here completely reverses the meaning.

"Or" here means, if you don't do thing X, then thing Y will happen. If you don't clean the surface, then the paint will not adhere.

"So" here means, if you do thing X, then this will cause thing Y to happen. If you clean the surface, then this will cause the paint to not adhere.

This is the exact opposite meaning. With "or", you are saying to clean the surface so that the paint WILL adhere. With "so", you are saying to clean the surface to prevent the paint from adhering. I presume that that is not what you want to say at all.


"Or" will be used before the sentence that its meaning is contrast to the previous sentence.

While "So" only used when the later sentence is the result of the prior sentence.

You must log in to answer this question.

Not the answer you're looking for? Browse other questions tagged .