You are being evaluated. Every word out of your mouth. Every e-mail. Every single Twitter.

Every time you speak, you are being personally judged by whoever hears you.
Every time you write, people rate your intelligence by what they read. You are “on the record” in their mind.
It’s not that the other people are jerks, snobs, or just plain mean. It’s just how we all process one another during any form of communication.
Whether we realize it or not, we all relate to one another (at some level) by the character of communication offered us. This is true in seeking a mate, in a college interview, a job interview, ordering coffee, doing e-mail, or yelling at someone who just cut you off in traffic.
Poor grammar, ding. Illogical word patterns, ding ding. Fluent cliche, ding ding ding. Obscene slang, ding ding ding.
It is fine to have a regional accent. Everyone is regional. Being true to your roots is a universal sign of character. BUT… the worst dings come from the poor grammar that is so often riding with the regional accents.
These verbal errors slip out of the most intelligent mouths, from time to time. That person loses status, at least subconciously, with others.
Often, many of us will even intentionally slur his/her language, trying to seem more “real.” Among close friends and relatives, people who know and (hopefully) love you, no problem. BUT… among strangers— especially among potential bosses or co-workers or professors or students— big problem!
Why does clear speech and writing matter?
No matter how good or bad they are, your ideas and opinions (badly expressed) will be automatically reduced to a lower level. Your crude or imprecise speech pattern has reduced you to a lower level of their expectation.
What is the best way out of this habit? (And speech is a habit, a pattern, a conditioning from childhood.)

STUDY ENGLISH.
Exploit your English classes to the utmost. There are so many excellent reasons why English can raise your life-long potential, and not just for earnings.
English is the global language of commerce and communication. This may change in time, as global societies and economies evolve, but right now it is English.
Read good books. Why are there “good” books? The stories, yes, but more, the WRITING.
Reading good writing can eventually comb the tangles out of your verbal brain center. Learn to love to read. Reading outside of class will speed up those skills and to build an effective vocabulary.
Read well and you will think well. Think well and you will communicate well. It becomes automatic.
Add (yes, add!) more English classes to your study load. English classes improve our communication skills in countless ways.
College-level English courses refine skills only half-learned in high school. Take literature, writing, and grammar as individual classes.
Good communication is essential to your climb up the ladder. The intellectual ladder is the first rung to your success in life.
While going after your degree, build your core ability to accurately give and follow instructions— to persuade people to a particular point of view, and to write in an organized and grammatically correct manner. This powerful ability will empower you throughout all areas of both your personal life and your business life.
With excellent communication skills, your ideas will be upgraded (not downgraded!) by others. Your clarity and demeanor will even build your own confidence!
The top-salaried occupations, then leadership roles, all require strong communication skills— the skills you will develop in ENGLISH classes!