In oral classes, teachers are often faced with all sorts oferrors made by students. Because of insufficient study of them,some correct all of the errors and some neglect them. The authorin this paper, through investigation of real class situation andall the possible collections of errors in his past teaching work,studies the errors and finds out four causes of the errors, andthen puts forward his suggestions for dealing with the differenterrors at different stages. In teaching students to speak English, teachers often find alot of errors in their speech. How should these errors be dealtwith properly? This is something many teachers are working at.Through investigation of real class situation and all the possiblecollections of errors in teaching work, it is believed that ateacher's knowledge of the learning law, careful observation ofthe errors being made by the students and proper attitudestoward the errors are very important. It has been found that when a child starts to learn his native language,he makes errors constantly, such as “This mammy chair”or “Mammy, apple eat” But he con say them correctly without much correction when he grows up. This is because “a human infant is born with an innate predisposition toacquire language”(Richards, 21). When an adult learns aforeign language, it is even more difficult, for physiologicallyhe has to train the muscles of his tongue and lips to get used tothe new ways of pronouncing a word, and psychologically hehas to receive new concepts of the language which are quitedifferent from his native tongue. Therefore, he unavoidablymakes errors in his speech. Even when he has mastered thelanguage to a certain degree, he still makes errors because “heknows very well what he should have done, but owing to thenervousness, tiredness, pressure and the effects of innertranslation (a kind of interference from home language), hejust lapses and forgets for a moment what to do” (McArthur,107-108). This doesn't mean that an adult makes more errors inlearning a foreign langu