A simple sentence is built from the minimum of a subject and a main verb. It can be very short in length (but doesn't have to be): 'The angry dog barks.' It puts across one simple idea: 'Rebecca sang.
Adding extra information to a sentence (or paragraph) using brackets, dashes or commas. If you take it out again, the passage should still make grammatical sense. "The case was worn - and very full - ...
The McMichael Canadian Art Collection announced the presentation of Early Days: Indigenous Art at the McMichael, following a landmark international tour with stops in Phoenix, AZ, Albuquerque, NM, ...