Scientists believe that they occurred during a short period of time in geological terms. (sciencedaily.com)
There are two times: if a teenager loses or gains a significant amount of weight during a short period of time. (brightonyourhealth.com)
Sometimes I start thinking about the man I used to be before having kids, and I always get so amazed at how much I have changed during this short period of time. (attachmentparenting.org)