While reading a book in English, every few lines of text, you run across a word or two that you don't know. You look up every new word in the dictionary. Bad move. All that does slow you down. Even electric or CD -ROM dictionaries can get in the way of your reading progress. A dictionary is like a road map. It can help you if you get lost and point you in the right direction. But if you stop to look at the "map" each time you take a step, you'll get nowhere fast. On your English learning "journey", a dictionary can be a helpful "travel companion "--if it is not overused. To help you start thinking in English, use an English-to-English dictionary. Otherwise, you will always depend on your native language and end up translating in your head. A good dictionary can help you do more than just find the meaning of a word. It can help you verify  spelling, check word forms and grammar usage, find example sentence and learn pronunciation. Some dictionaries even provide exercises to teach you how to use their resources. Take time to get to know your dictionary. Learn the pronunciation symbols. Understand what the abbreviations   mean. Try to master the important grammar rules. Look for charts, diagrams and lists might be useful in the future. You will discover how helpful it can be to make friends with your dictionary. And as they say, "A friend in need is a friend indeed." Why do we need a good English-to-English dictionary?
Because it is a good friend. Because it can help us to find the right direction if we get lost. Without it we'll always depend on our native language and end up translating in our head. Because it can help us to start thinking in English and in Chinese.