Is there a way for "SAVE" the progress on a long questionnaire?

Can a client SAVE their answers on a questionnaire and come back later to it if they dont have time to complete? 

You can enable the autofill settings of your form. This way, any information entered by the user shall be saved on the cookies of his browser. After he leaves the page and gets back, the information on his view will fill up again so he can continue with the form. You can check this guide to know how to enable this setting on your form: https://www.jotform.com/help/227-How-to-Enable-Auto-Fill-on-Forms

If you have questions, please let us know.