Manipulation is the act of artificially inflating or deflating the price of a security. In most cases, manipulation is illegal. It is much easier to manipulate the share price of smaller companies, such as penny stocks, because they are not as closely watched by analysts as the medium- and large-sized firms. Also known as price manipulation..
A compound sentence contains two simple sentences joined by a coordinating conjunction. This been a better choice for compound sentence has two more subjects or has two more verbs or 110,255 results
This last type of compound sentence is the one we will concentrate on for comma use. A compound sentence must have two independent clauses  not just two verbs, two nouns, or two groups of words that are not independent clauses. Look at this example. In the above example, two verb groups are being joined by and.