题目

完形填空 There was once a lazy crow(乌鸦). He thought it was too much trouble to 1 food. “Caw! Caw!” he said. “If someone brought me my food every day, I'd be very 2!” One day, he saw a(n) 3 pigeon(鸽子) flying by. “How happy and well-fed it looks,” the crow said to himself. So the craw 4 the pigeon until they came to a 5. There were some other 6 there too. Before long, an old man came along and brought them a large bag of food. When the man had gone, the crow flew over to the pigeons. “Caw! Caw! ”said he. “Can I 7 you?” “No, you can't !” 8 the pigeons angrily. 下列说法正确的是 A．石英广泛应用于光纤通讯 B．工艺师用盐酸雕刻石英制作艺术品 C．水晶项链和瓷器都是硅酸盐制品       D．粗硅制高纯硅不涉及氧化还原反应