Rules of error-free speaking and writing
1-Use simple language. Some beginners try to build very complicated sentences with things like the present perfect tense or conditionals. They make horrible mistakes. 't do this! If you've just started to speak or write in English, you should say what you can say (simple sentences that you have seen many times) — not what you want to say (complicated sentences). You may feel you're talking like a child or that you are not expressing your thoughts, but don't worry about it. Right now, your task is not to express your thoughts freely; your task is to learn the language.
2-Be slow and careful. In the beginning, you should write very slowly. If you need 2 hours to write an e-mail message with 10 correct sentences, that's okay. That's how long it should take if you're just starting to write.
Why should it take so long? Because you should read your sentences many times, looking for mistakes. You should correct your own sentences frequently. You should check if your sentences are correct by using a dictionary and the Web. And you should look for example sentences to imitate.
When you're speaking, it's okay to build a sentence for some time in your head before you open your mouth.
3-If you're not sure how to say something, don't say it. If you can't say something correctly, it's almost always better not to say it. You don't want to teach yourself the wrong way to say it. You can try to look for the correct sentence in a dictionary or on the Web (see next point), but when speaking, usually you don't have time for that. So it's a good idea to say something else — something that you know is correct. It can even be something on a different subject.
4-When writing, always look things up. Whenever you're not sure how to use a word, look it up in a good dictionary to find example sentences with it. When you've written something, and you are not sure if it's correct, search for it on the Web with Google. If many pages contain your phrase, then it is probably correct. Dictionaries and Google should be your everyday tools, and you should use them even many times in one sentence (especially if you've just begun writing in English).
5-Know where you can screw up. Sometimes learners don't even realize how different English
is from their native language. When speaking, they translate word for word from their native language, and they think their sentences are okay.
When reading or listening in English, pay close attention to things like word order, articles, prepositions, and tenses. Compare sentences in English
with equivalent sentences in your native language. Notice the differences in words and in word order. This will make you more careful when speaking in the foreign language, because you will realize which parts of your sentences can be wrong and should be double-checked.