They change shape due to a number of reasons.
The easiest reason to understand why they change is that they erode.
The coasts around the the world erode due to waves hitting cliffs, the wind batting against the coasts etc. Over a long period of time we can see that they change in shape.
(sorry I don't know why they move)
<span>He is bigger and stronger than anyone else.</span>
The correct answer is <em>Malala was right about the edict and what it meant</em> AND<em> She was a global symbol of girls’ rights but also just a kid.</em>