Correct the speling and gramatical mistake of given document.
The Document is:-
The online service like Facebook, Twitter and Instagram should be free. This is because the company of online service will be able to gain the amount of advertising fees by connecting with the company which sells products via like these SNS. It means that the more the sales of these products are increasing, the more adverting fees will increase at the same time. On the other hand, if these SNS are not free, the selling companies will hesitate to post their products on this SNS and as a result, SNS companies will lose the benefit of advertising. In this point, the online service should be free.
And on the relationship for selling products, there is the existence people should not forget. This is the people who actually see and decide to buy these products. On this relationship, they should be the general users of these online users. Of course, on the side of general users, it is important that the online service is free. This is because the free online service relate to the increase of possibility of people who see advertising of the products on SNS. It means that the more general users increase, the more the sales of their products will increase. It is evident that the online service should be free also for the general users in consideration with this point.
As people can suppose from these two observations, it is obvious that free Online service has a positive effect for both of their own companies, advertising companies, product companies and the general users of SNS. So, I think online service should be free.