1．A shark (鲨鱼) dived down and swam under the boat.
2．On this fish, one eye is abnormal, while this one has defects on its fin (鱼鳍)．
3．The first day began early at a_dive_ (潜水) shop in Cairns.
4．This way you'll feel a sense of achievement each time you hit your target (目标), which will keep you motivated.
5．Critical thinking is an attitude (看法，态度) as much as an activity.
6．It scared (使惊恐) him to realize how close he had come to losing everything.
