A:①是因为光的折射,水中“筷子”(侧面看)是水中筷子的放大、正立的虚像
B:②是因为光的直线传播,墙上“手影”是手经过小孔所成的实像
C:③是因为光的反射,“彩虹”是太阳光发生色散后的单色光排列
D:④是因为光的反射,“倒影”是白鹤在水面成等大、倒立的虚像
地理信息系统在城市环境管理中的应用领域有( )
①城市环境规划与决策 ②城市路网规划 ③城市环境监测与评价
④城市道路交通管理 ⑤城市环境预测与模拟
一共有多少人跳绳?
加法算式:
乘法算式:
完形填空
Look at thephoto. It's my family. The old man and the old woman are my 1. This is my father. He is next to(挨着) his brother, my 2. This woman is my mother. She is my English teacher. You can 3 three children(孩子) in the photo. These two girls are my4. The girl in a red dress is Nancy5 the girl in a yellow dress is Susan. Do you know the boy? Yes, it's me.
My grandparents are in the USA. I am in Beijing 6 my parents now. My father is 7 teacher. He works in Beijing No. 28 Middle School. He often has milk 8 breakfast. And he likes to eat 9. My mother often 10 some eggs and a glass of milk. I have a big family.
“我住江之头,君住江之尾…山山皆向北,条条南流水”,描述的地理特征是( )