2。2。2 Swain's Comprehensible Output Hypothesis

Merrill Swain (1995) criticized Krashen for neglecting the significance of comprehensible output and proposed “Comprehensible Output Hypothesis”。 Swain’s hypothesis is based on the observation of the immersion programs many years, which aims at satisfying children’s bilingual demands。 Swain argued that students have little opportunities to produce target language and that students lack enough motivations to output are the main reasons why learners are unable to achieve second language proficiency。 Swain claimed that comprehensive output facilitates learners to develop linguistic competence and entitled such meaningful output with using target language as “pushed language use”。 Such output has more than four functions on learners’ SLA。 First, output can stimulate hypothesis testing for learners to try out grammar rules which they have not mastered yet。 Also, output can promote consciousness-raising by reminding the learners of the gap between inter-language and target language, which lead learners “to recognize what they do not know, or only know partially” (Swain 1995: 125)。 Moreover, output can assist the learners moving from semantic processing to syntactic processing and at last output can help learners generate more comprehensible input through meaning negotiation with their interlocutors。

2。2。3 Long's Interaction Hypothesis

Some linguists claimed that learners can acquire target language only after achieving interaction modifications。 Long (1983) extended input hypothesis theory and proposed interaction hypothesis, which admitted the importance of comprehensible input in language learning but placed more emphasis on the function of the interaction modifications which were used to negotiate meaning when conversation difficulties occurred。 In Long’s perspective, the more adjustments conversation participants make to negotiate meanings, the more progress probably will be made for the acquisition of target language。 One of the participants in a conversation will say something that the other does not understand; the participants will then use various communicative strategies to help the interaction progress。 The strategies used when negotiating meaning may include slowing down speech, speaking more deliberately, requests for clarification or repair of speech, or paraphrases (H。 Douglas Brown 2000: 287-288)。 Thus, the learners will care about the form in context of meaning and attempt to make comprehensible production so as to maintain the conversation to proceed and at last language acquisition is accomplished。

Since for most Chinese non-English major students College English classroom is the main environment to receive and produce English, it is not incomprehensible to conclude that teacher talk is the main resource of the target language。 Moreover, with student-focus theory advocated, instructional techniques: inquiry and discovery learning are widely adopted by language teachers based on tasked-based teaching approach or communicative teaching approach。 Thereby, interaction opportunities and the frequency of student talk are good indicators of levels of student involvement and output opportunities。 

2。3 Learning motivation in the classroom

2。3。1 Definition of motivation

The behaviorists regarded motivation as the anticipation of reinforcement。 In Skinner’s conditioning model, creatures may act desired behaviors for anticipated rewards。 David Ausubel (1968), a cognitive psychologist, elaborated that motivation is derived from six basic innate drives, namely exploration, manipulation, activity, stimulation, knowledge and ego enhancement, which compel learners to fulfill the target。 Abraham Maslow (1970) proposed a pyramid of human’s needs and viewed that after reaching the lower needs, human are motivated to pursue the higher needs。 Hunt (1971) indicated that autonomy of people to make choices spurred motivation to the highest level。 In addition, motivation can be considered in constructive way, which shows motivation relating with not only personal choice but also social context (Williams & Burden 1997)。