They built strong walls round the town as a______against the enemy.A．defenseB．defendC．defe

A．Fifty underground stations were made waterproof.B．A flood wall was built.C．An alarm

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A．They shine brightly.B．They are extremely strong.C．They can store heat.D．They can abs

A．50 underground stations were made waterproof.B．A flood wall was built.C．An alarm sys

听力原文：（A)The houses are built with a same design.（B)The man is leaning on the wall.（C)T

They chose only the strong mountaineers t