Exit or Save button with partial completion

Hi,

Is there a way to create (exit & save) button directed the respondent to exit page but with saving the current answer and the respondents can come back later to continue the survey at the same loop?
the survey will be emailed to previous known respondents so the link will be unique but I want them to exit the survey and continue in later day at the question where they stop at it which is a loop and merge question..
Thanks,