Please read my publication and find your answer.

@Changhong, are there any existing motivation like factors in your course opinion surveys or school assessments? These would make a large sample and be readily available to examine. They dont have to say motivation, maybe related concepts like interest, active participation, etc.

Also, are the courses partly online? If so I have used learning analytics to assess motivation and outcomes. I have quite a few papers on this, as cited below . Hope this helps. Ken

learning analytics predict student outcomes? Journal of Educational Technology Systems, 44(3), 273-299. Sage

Strang, K.D. (2015). Effectiveness of instructor-led collaborative learning in the classroom. Journal ofEmerald Literati Award Highly Recommended Applied Research in Higher Education, 7(2), 1-16. Emerald Literati Award

I do not have an instrument for motivation in reading and listening skills. If you cannot find one, you may have to create one yourself. That would mean doing a pilot study to assess reliability and validity, so it would make your study more complicated, but many researchers do this if they cannot find a study they can adapt.

Dear Changhong Peng,

For reading, there is the Motivations for Reading Questionnaire (MRQ), which was originally intended for children (check the links below). You could adapt this instrument to use with an elderly population, or you could always devise your own questionnaire.

Cheers,

https://files.eric.ed.gov/fulltext/ED394137.pdf

https://learninglab.uni-due.de/research-instrument/14027

I recommend you read this article:

Kim, K.J. Reading motivation in two languages: an examination of EFL college students in Korea. Read Writ 24, 861–881 (2011). https://doi.org/10.1007/s11145-010-9229-z