Sentence Fragment: frag 
You might be very surprised when your teacher¡¦s face turn blue on putting down this comment.  What is wrong? You are making a frequently made but absolutely unacceptable mistake!  

Do you remember what a sentence is? Right! A sentence consists of a SUBJECT and a PREDICATE.  Without either of them, you are making a fragment.  Usually, fragments are actually clauses or phrases, not sentences.

Here are some helpful sites to help you improve your sentence skill:
 [Course Description] [Syllabus] [Handouts] [Relevant Links 
[Cultural Connections] [Web Class] [Internet_Course Page 
[English Dept.] [Fu Jen University]