関連ワード:  give two examples of artificial light    give some examples of artificial light    what are some examples of artificial light sources    give two examples of artificial source of light    give two examples of natural and artificial light    give two examples of man made sources of light    two examples of artificial light sources    give two examples of each artificial source of light    give three examples of artificial light    give five examples of artificial light  
結果 : give two examples of artificial light