3Sweller J. Cognitive load during problem solving: Effects on learning [J]. Cognitive Science, 1988, (12) :257 - 285.
4Gary JOckey. Construct implications of including still image or video in computer - based listening tests [J]. Language Testing, 2007, (24) :517 -537.
5Bejar I, Douglas D, Jamieson J, Nissan S, Turner J. TOEFL 2000 listening framework: A working paper[ M ]. Princeton, NJ : Educational Testing Service,2000.
6Guichon N, McLornan S. The effects of multimodality on I2 learners: Implications for CALL resource design [ J ]. System, 2008, (36) : 85 - 93.
7Coniam D. The use of audio or video comprehension as an assessment instrument in the certification of English lan- guage teachers: A case study [J]. System, 2000, (29) : 1 - 14.
8Sueyoshi A, Hardison D M. The role of gestures and fa- cial cues in second language listening comprehension [J]. Language Learning, 2005, 55(4) :661 -699.
