Light and shadow (影子) are friends. They usually go together. We receive light every day. __________小题1:________________

Light cannot shine through you. ___________小题2:________________ There is a spot(斑点) on the ground next to you. The light cannot reach the dark spot. This is your shadow. 

______________小题3:_____________Your body stops very little light from reaching the ground. So your shadow is quite short.  

But in early morning or late afternoon the sun is low in the sky. The light moves over more of your body. ___________小题4:_________________ Your body keeps a lot of light from reaching the ground. 

We love light, especially sunlight. _____________小题5:______________Most of us like to stand in the shadow of a tree in summer. But some people are afraid of their own shadow at night. They do not want to walk in a dark street. They do not want to see the shadow, either. But still light and shadow usually go together.

球罐附属装置有哪些检查要领书？