[etni] Listening in module E - "serious grammar errors" ???

In the module E listening, the answer key for the bagrut says to take off one point for "serious grammar error". 

Could someone who marks bagrut tests elaborate on this?
For example - should we take off the point in the following cases: 

1) misuse of a / an ("It was a awful ride" )
2) tenses ("She goes to Kenya.", when it should be "She went to Kenya.")
3) missing s in 3rd person singular present simple ("He read the book." ) "He read's the book." would be a spelling mistake and no points would be deducted, right?
4.) unneeded s in present simple ("They reads a lot of books.")
Any other examples of exactly what a "serious grammar error" is? 

                                      Shabat Shalom
                              sara g
sara g in israel
             sarag@xxxxxxxxxxxxxxxx
and also saragabai@xxxxxxxxx
Visit us at The E Zone
     http://c3.ort.org.il/ganyavneenglish

-----------------------------------------------
Read "The Etni Rag" - http://www.etni.org/etnirag/

Add yourself / Update your entry to "Who's Who on Etni"
http://www.boker.org.il/etni/whoswho.htm
-----------------------------------------------

Other related posts: