Translation of breastbone in Spanish

Will you be online in 1 hour? I saw your translations and had some comments: rainbow is it 'arco iris' or one word arcoisris? Usually all words appear lower case. Sometimes it is uppercase. It all depends.
The snow can be compared with white veil. Here in Davos, there is lots of new snow, so fresh and powdery snow, which is great for skiing. One needs to be careful from unexpected avalanches.
If you are spell checking my letters, that would be great. I would then do the same with your letters. Can you please correct this email too? I thank you in advance for helping my Spanish.