2.2. Basic elements of CL 

    There are three kinds of understandings about the essential elements of CL.The first one proposed by Slavin(1995) believes that group goals,inpidual accountability and equal opportunity for success are the three basic elements of CL.The second one is four-element theory put forward by Cohen.E(1994) and it holds that four elements consist of group formation and management,task design,social component and exploratory task.And the third one is the most widely accepted theory published by Johnson and Johnson in 1994 (Johnson, Johnson, 1994). The following are the 5 elements :

A. Positive Interdependence

    It is the first and the most important element of CL served as motivation to encourage students work together in small groups to make joint efforts to make sure the successful performance of all its inpidual members in group,which benefits both the inpiduals and the whole group.

B. Face-to-face Interaction

    It promotes students’ abilities to listen for opinions, share their own ideas,discuss with each other,encourage with supports and help each other through interaction, as well as a means of building up social interpersonal relationship in face-to-face interaction.