The tower of Pisa has never been upright. Its leaning can date back to the time not long after it was built in 1173. First, the tower tilted towards the north. Then during the prolonged process of construction till 1370, the tower had always been leaning to the south.
Throughout the monument s history, many efforts have been made to halt the lean. These efforts have so far helped prevented the tower from topping over. But since 1911, the offset at the top of the tower has increased at a fairly consistent rate. Shortly after 1989, for the sake of safety, the tower at Pisa was closed to visitors.
In 1990, a special commission was organized to find new ways to save the tower. At first the commission worked mainly on the outside of the tower, but in the next few months, more radical techniques will be tried to stop the tower s lean. The ultimate goal is not to straighten the tower but to ease its top back a little. With luck, the landmark can stand into the next century.
四年级作文:Our School
小学四年级英语作文:暑期难忘的一件事
小学四年级英语作文:我的家庭照片 A Photo of My Family
四年级英语作文:My favorite season
四年级英语作文:Everyday of mine
四年级作文:My Favourite Book
小学四年级英语作文:去超市 Go to the supermarket
小学四年级英语作文:我们的学校 Our School
小学四年级英语作文:我喜欢秋天 I like autumn
四年级英语作文:Friendship
小学四年级英语作文:家乡的天空 Sky in my hometown
四年级英语作文:Animals
小学四年级英语作文:我梦想的工作 My dream job
小学四年级英语作文:我爱我的卧室 I love my bedroom
小学四年级英语作文:I like autumn
四年级英语作文:I love my dog
四年级英语作文:What is success?
四年级英语作文:The Tree in Front of My House
四年级作文:How to be a Model Student
四年级英语作文:Birthday 生日
小学四年级英语作文:动物 Animal
小学四年级英语作文:我爱我的狗 I love my dog
四年级作文:Do you like me?
小学四年级英语作文:一场大火A big fire
小学四年级英语作文:我的小兔子 My Little Rabbits
四年级英语作文:My English Teacher
四年级作文:我的小兔子
四年级英语作文:Student of the week
四年级作文:animals
四年级作文:一场大火
不限 |
英语教案 |
英语课件 |
英语试题 |
不限 |
不限 |
上册 |
下册 |
不限 |