Wrong. He began as office boy but in no long time they made him timekeeper.
Right. He began as office boy, but in no long time they made him timekeeper.
808. Use a comma between clauses joined by the conjunction for.
Wrong. He went into the house for his automobile needed water.
Right. He went into the house, for his automobile needed water.
809. Use a comma between short co-ordinate clauses not joined by conjunctions, if the clauses are parallel in structure.
The horse neighed, the pig grunted, the dog barked.
810. Use a comma after a dependent clause that precedes a main clause.
When he speaks, we all listen.