The Snipe and the Clam（在线收听）

    Just as a clam came out to bask in the sun a snipe pecked at its flesh．The clam closed its shell and squeezed the snipe's beak．“If it does not rain today and it does not rain tomorrow，you will be a dead clam，”said the snipe．If you cannot free yourself today and you cannot free yourself tomorrow，you will be a dead snipe，”replied the clam．Neither would give way and eventually a fisherman caught both the clam and the snipe．Exercises：
    回答下列问题：
    ① What happened to a clam when it came out to bask in the sun？
    ② What did a fisherman catch？
    ③ Why could the fisherman catch both the clam and the snipe？