The best way to learn English quickly is to jump in at the deep end!
You need to immerse yourself in English. In other words, you need to be in an all-English environment. Learning English through textbooks is a good start; however, it's important to remember that the way English is spoken, is often very different from the way it's written. In the real-world, the grammar rules that you have learned go straight out the window! You will realise that casual, spoken English follows its own set of rules (or none at all)! You'll benefit incredibly from being somewhere where you MUST use your English.
Isn't it about time that you made that long planned trip to an English speaking country?
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Link: Quick Tip - Thinking in English
