渔夫的妻子桑娜坐在火炉旁补一张破帆。屋外寒风呼啸，汹涌澎湃的海浪拍击着海岸，溅起一阵阵浪花。海上正起着风暴，外面又黑又冷，这间渔家的小屋里却温暖而舒适。地扫得干干净净，炉子里的火还没有熄，食具在搁板上闪闪发亮。挂着白色帐子的床上，五个孩子正在海风呼啸声中安静地睡着。丈夫清早驾着小船出海，这时候还没有回来。桑娜听着波涛的轰鸣和狂风的怒吼，感到心惊肉跳。

    古老的钟发哑地敲了十下，十一下……始终不见丈夫回来。桑娜沉思：丈夫不顾惜身体，冒着寒冷和风暴出去打鱼，她自己也从早到晚地干活，还只能勉强填饱肚子。孩子们没有鞋穿，不论冬夏都光着脚跑来跑去；吃的是黑面包，菜只有鱼。不过，感谢上帝，孩子们都还健康。没什么可抱怨的。桑娜倾听着风暴的声音，“他现在在哪儿？上帝啊，保佑他，救救他，开开恩吧！”她一面自言自语，一面在胸前画着十字。

 下列透镜中，属于凹透镜的是（　　）

其他星星围绕着北极星在逆时针的运动。

    On a clear February morning, a California black bear was set free. Looking around, he ____(skillful) climbed the nearest tree. From high above the ground, he could see the hundreds of acres____were now his home. His eyes were filled with ____(curious)

    The bear had come a long way. Last fall, the seven-month-old bear bub(幼兽) was found all alone. He had no mother to care for him. He was thin,____ (weight) only 20 pounds----about half the normal weight for a bear that age. Luckily the bub____(bring) to The Fund for Animals Wildlife Center in Ramona, California. At the center, the bub shared____ outdoor enclosure(围栏) with another bear. There were trees to climb and places for them to dig dens(兽穴).____ (teach) the cub to find his own food, people working at the center ____(hide) fruit in tree branches. Soon, the bear was an expert at climbing trees and "picking" the fruit. All the staff felt____(amaze) at his adaptability.

    Finally, the day had come. With his new skill and strong body, the bub was ready to be____his own, and ready to live like a bear should--- in the wild.

- What's in the classroom? (    )

- Two doors and _____  chairs.