Why is speaking important?
When we talk about speaking in class it is important to differentiate between the kind of speaking which occurs in mechanical drills and repetition, on the one hand, and situations where students use as much language as they can and where getting their message across is just as important as grammatical accuracy, on the other. In this article it is the latter kind of speaking that we are going to look at. (来源：英语麦当劳－英语杂志 http://www.EnglishCN.com)
There are three main reasons why it is important to encourage students to speak as fluently as possible. In the first place, speaking activities give them a chance for rehearsal - practising the real skill of speaking as a preparation for using it outside the classroom. Secondly, when students speak using all and any language they know, it provides valuable feedback about their language knowledge, for both them and their teachers. How well can they perform in spontaneous conversational situations? What do they seem to know? What are they finding difficult to achieve? Lastly, good speaking activities provoke genuine student engagement where they really get involved with the process of language learning in class.
What is good speaking material?
Good speaking activities should have a number of characteristics: they should engage the students by making them want to take part. They should have some purpose which is not purely linguistic - such as solving a problem or reaching a decision. They should be designed to maximise the range of language they will use, so they should not restrict students, for example, to specific grammar patterns.
What kinds of speaking activity can we use?
A popular kind of speaking activity involves an information gap. Students have different information and they have to solve a problem by swapping facts to bridge the information gap between them. Typical examples include situations where four students have each seen separate pictures: by telling each other what they have seen, they are able to work out the story that the pictures tell. In another type, one student has a picture that another student has to draw only by listening to a description of it.
Another kind of activity which provokes the kind of speaking we are considering, involves the students in conducting surveys. These can be on any subject: they can question each other about their daily lives (habits, family,) or preferences (food, films, books). Questionnaires and surveys can fit into a longer teaching sequence so that planning the questionnaire and collating the results afterwards can be valuable language-learning activities in themselves.
Discussions provide ideal opportunities for speaking. Subjects with scope for controversy are best for discussion: roles of men and women, censorship, animal rights, patriotism, for example. Many people have plenty to say on such topics. Some of the most enjoyable classes of all are ones when unplanned discussions suddenly arise on issues that matter to the students.
But most teachers will also be able to remember discussions that simply did not work, despite a seemingly good topic. This may be because it is unrealistic to expect someone to discourse fluently in a foreign language without any warning, formulating deeply-held opinions quickly in front of fifteen, twenty-five or more fellow students. It is not enough, in other words, to ask students, 'What do you think of X?'. Instead, teachers should plan the discussion sequence giving students material to react to, and time to plan what they are going to say.
A popular way of emphasising the rehearsal aspect of speaking activities is to use simulations and role plays. This is where students pretend that they are in a different situation, either as themselves or playing the role of someone quite different. We could ask them to be guests at some party and go there as different characters. We might clear the classroom so there is an open space for them to party in. They could, as themselves, pretend to be at an airport trying to check in luggage, or either as themselves or another character take part in a television programme. In all these cases the students are using language in order to participate in the activity rather than the other way round! Some students find it very comforting to use language in a simulated environment, playing the role of someone else - it allows them to experiment more freely than they ordinarily would.
When should students speak?
Many people have thought that speaking activities should come at the end of a teaching sequence; you have taught the present continuous for future, for example, and now you ask students to role-play situations in which they make arrangements and invite each other: (What are you doing this evening? How about coming to a movie? etc.). There is nothing wrong with this of course, but it should not be thought that there has to be that kind of linear relationship between a speaking activity and non-speaking material that went before it. Indeed, students probably need quite some time for new language to sink in before they can produce it spontaneously in conversation.