33. A Deadly Current p.213
     it is a pity that every summer a few people drown at the beach. In some cases, these people were good swimmers. So how did it happen？ Riptide！
     Riptide is a strong underwater current. It moves quickly away from shore and out to sea. It appears suddenly and pulls its victim under and far off shore. Therefore, people should make it a rule never to swim too far out from the beach.
     If you find yourself in a riptide, don't panic. And by no means should you try to go against the tide and swim back to shore. You'll tire yourself out and probably drown. Instead, swim parallel to the beach. A riptide is very narrow. So just a few strokes in the right direction and you'll be out of danger.
     be all ears 洗耳恭聽
     You are dead right. 對極了 dead adv.絕對地，完全地 deadly 致命的
     be at sea When we talked about business, I was at sea. I am puzzled by what you said.
     I make it a rule to get off early.
     be in the habit of
     By no means is he nice. By no means did he tell the truth.
     instead, …… = on the contrary
     stroke n.（游泳的）劃