joy in all kinds of parties in our school. (I will join in all kinds of parties in our school.).
The learners know the difference between joy and join. The error here seems to be caused
by the learner's carelessness. In detail, in this study, spelling errors can be classified into
omission, overinclusion, misselection, misordering, blending and adding.
 
(1) Misselection
Misselection errors are the most common spelling errors in students' writing. It takes
account of 31 .88% of spelling errors. Students write some letters into the wrong one
causing the misselection errors. Sometimes the students know the pronunciation of the   
words, but wrongly spell the words according to phonological rules they have learned. For
example, the spelling errors such as  fause (false),  necesary (necessary),  waist (waste),
morden (modern),  convanient (convenient),  essencial (essential) belong to this kind of
errors.  But there are also some errors that seem to be caused by the students'
mispronunciation, such as  prograss (progress),  attitute (attitude),  expecially (especially).
However, it is difficult to identify whether the student mispronounces the word or he  just
has a rough idea about the word. For example,  hostital (hospital),  attitute (attitude)，
disturbe (disturb)，crimy (crime). However, one point is clear that there exists similarity
between the misspelled word and the target word. 非英语专业学生英语写作中的词汇错误分析与对策(5):http://www.youerw.com/yingyu/lunwen_4257.html