Here is a worksheet on the Greek word roots mega, megal/o, and megaly. They mean large, great, and million. Once again, this is a very productive root in English, yielding words like megaton, megalomaniac, and megabyte.
If you find typos in this document, I would appreciate a notification. And, as always, if you find this material useful in your practice, I would be grateful to hear what you think of it. I seek your peer review.