Hi Mohamed Elsaid,
Could you share with us what you're researching and in what context? i.e. if you're doing the research alone, in a research group, at a university, etc. 
Also, is it really necessary to make emails a mandatory field? Without an explanation of why you need it, this requirement puts me off completing the survey, and other people may feel the same way.

Hi Emma,

Thank you very much for your reply. I am doing the research as part of my Master degree Thesis at USM University (Malaysia). The field of study is translation studies, with focus on using SDL Trados as one of translation memory CAT programs. I am doing the study alone.

The questionnaire collects quantitative data only. I will need to make interviews with selected participants to collect qualitative data. This is the reason I made the email address filed mandatory (to be able to contact the selected participants). I confirm all participates data  will remain confidential. I will add this in the questionnaire descriptive part in the first page now. Thank you very much for flagging it. 

Hi Emma,

Thank you very much for your reply. I am doing the research as part of my Master degree Thesis at USM University (Malaysia). The field of study is translation studies, with focus on using SDL Trados as one of translation memory CAT programs. I am doing the study alone.

The questionnaire collects quantitative data only. I will need to make interviews with selected participants to collect qualitative data. This is the reason I made the email address filed mandatory (to be able to contact the selected participants). I confirm all participates data  will remain confidential. I will add this in the questionnaire descriptive part in the first page now. Thank you very much for flagging it.