Bad Reasons
It is important too choose grammar points relevant for the student needs. The native speakers generally gave higher marks to mistakes which impeded their understanding..

It's tidy:
Vocabulary remains a big muddle.Pronunciation is more easily analysed , pronunciation is that part of a student which is the same at the end of a lnguage course a at the beginning.

It's testable
A good test can tell you how you are doing, whether you have learnt what you wanted to, ans what level you have reached. Tests show whether students are learning and whether teachage ers are teaching properly, they ranks learners.

Grammar as a security blanket
Grammar rules shine out like beacones giving students the feeling that they can undrstand and control what is going out.

tesch the whole system
it is more relistic to regard grammar as an accumulation of different elements.We should teach using the following quistions,

• How much of this students know already from their native language?
• How much of the rest is important?
• How much of that have we got timme for?

Power
Societies like grammar.Grammar involves rules, and rules determine 'correct' behavior. In more  authoritarian societies, students are more likely to sit in rows, listen, learn rules, do grammar exercises, make mistakes and get corrected. Examination syllabi the world over also generally include a component which requires great mental agility.

Results
Students do not learn English, they learn grammar, when it comes to using the language in practice, they discover that they lack vital elements, typically vocabularyand fluency. They can recite irregular verbs cannot sustain a conversation.

With those techniquesyou are not teaching a new language you are only teaching grmmar, and your sstudentes are going to notice that when they have to produce the language}