横向
1
Second lightest element
4
Curved glass that refracts light
7
Path of a planet around the sun
8
Our home planet
9
Preserved remains of ancient life
11
Push or pull on an object
纵向
2
Substance with pH below 7
3
Center of an atom or cell
5
Chemical element in table salt
6
Group of similar cells
10
Positive particle in nucleus