If you still have a lot of tension and stiffness within your tongue, you will have a long way to go to your destinations as good enough. The problem is so easy to speak English without being under pressure in Vietnam if you do project any sort of pressure or tension during your speech, you will get a fist into your face haha..! Học tiếng anh nhiều quá cũng không tốt bởi mình người việt.