can some body give me a example of a clause sentence
Eric or Bear or whoever --
If you have one independent clause, you also have a sentence if you punctuate it properly.
If you have one dependent clause, however, you have a sentence fragment.
If you have two independent clauses, joined properly, you have a compound sentence.
If you have an independent clause and at least one dependent clause, you have a complex sentence.
There are many examples in the link given above.