1896年,法国科学家贝克勒尔在一种铀盐中发现了铀元素的()放射性。它能使不透光的()暴光。
参考答案:天然;底片
根据汉语填写适当单词,使句意完整
1. Of all the sports, Kitty likes __________(羽毛球) best.
2. My uncle likes to go to different kinds of __________(图书馆) all over the world.
3. There are twelve __________(月份) in a year.
4. This is one of the biggest __________(餐馆) in Beijing.
5. Why not help the old people __________(穿过) the road?
6. The clothes over there are the __________(运动员) in our school basketball team.
7. On my birthday, my mother always __________(买) presents for me.
8. My classmates think that Millie is a __________(苗条的) girl.
9. This music __________(听起来) so beautiful.
10. Sim on and Daniel enjoy __________(放) kites in the park at the weekend.
发展载人航天,其重要现实意义是( )。
A.培养科技队伍
B.增强国家综合国力
C.增强民族自豪感和凝聚力
D.促进科技进步
E.提高国家威望