please read the following article

Teng, F. (2015). Involvement load in translation tasks and EFL vocabulary learning. The New English Teacher, 9(1), 83-101. Available at: http://www.assumptionjournal.au.edu/index.php/newEnglishTeacher

Here is the article:

Folse, K.S. (2006). The effect of type of written exercise on L2 vocabulary retention. TESOL Quarterly, 40, 273–293.

Huang, S., Eslami, Z., & Willson, V. The effects of task involvement load on L2 incidental vocabulary learning: A meta-analytic study. The Modern Language Journal, 96 (4), 544-557.

Keating, G.D. (2008). Task effectiveness and word learning in a second language: The involvement load hypothesis on trial. Language Teaching Research, 12 (3), 365-386.

Kim, Y. (2008). The role of task-induced involvement and learner proficiency in L2 vocabulary acquisition. Language Learning, 58 (2), 285-325.

Laufer, B., & Hulstijn, J. H. (2001). Incidental vocabulary acquisition in a second language: The construct of task-induced involvement. Applied Linguistics, 22, 1–26.

 Based on the memory research on desirable difficulties and spread of activation, the more times someone encounters the same information in different contexts, the easier it is for that information to be retrieved at a later date.  There are various memory studies that explain why the task-induced involvement construct enhances vocabulary learning.  There is also evidence that embedded and extended vocabulary instruction enhances vocabulary learning.  See Nagy.

Send you two articles. 

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