Plurals, possesives, thesis statements, and focus points can all become problems to a young writer without the proper research.  Knowing and getting a concept of what these are before the writing process can save alot of time and reduce the amount of red marks on a paper.  The apostrophe is optional when using plurals but the possesives have to be specified as just that.
    The thesis statement is a single sentence of the central or main idea of a paper.  Know this, how to form a thesis, what it takes to support it, and how to incorporate it into your paper.
    When writing a paper you should stay focused on the title and not venture far from it.  The ability to stay around the subject comes from careful planning with outlines, proofreading and rough drafts.  Research your subject so that you will know it first hand which will give you the ability to let your paper flow instead of state facts and jump from point to point. 


Example of thesis statement: Title:Unix: The Premier Operating System Thesis:Unixs' proven track record of being stable, its' performance, portability, and how it addresses security issues proves in more ways than one that it is the premier operating system.

Example of plurals and possesives: Plural:The United States has many enemies. Possesive:The United States' government is apprehending offenders of terrorist crimes at an alarming rate.

Sources: Diana Hacker."A Writer's Reference." Fifth edition. www.dianahacker.com/writersref

Macon State Collete Online Writing Lab http://media.maconstate.edu/owl/home.asp

http://www.hut.fi/~rvilmi/help/grammar_help/