An independent clause is a group of words made up of a subject and a predicate. It expresses a complete thought. It is also known as a main clause.
- I know milk is good for me.
(complete thought/milk is good for me)
- He was late for work.
(complete thought/late for work)
- The mountains in Switzerland are beautiful.
(complete thought/beautiful mountains in Switzerland)
Compare with a dependant clause.