横向
1
Mass per unit volume
5
Blocking of light by a celestial body
6
Path of a planet around the sun
10
Force that attracts objects together
11
Disturbance that transfers energy
13
Compound containing oxygen
纵向
2
Second lightest element
3
Group of similar cells
4
Icy body with a tail near the sun
7
Substance with pH below 7
8
Unit of force
9
Infectious microscopic agent
12
Positive particle in nucleus