1. I will be a musician one day.

Question

2. I will be a musician some day.
(Which one is correct? Are both OK? Then which one is commonly used?)

3. She is putting on cosmetics on her face.
4. She is wearing cosmetics on her face.
5. She is puting on makeup on her face.
6. She is wearing makeup on her face.
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Thank you for your help. Which ones are grammatical?

Answer 1

1 and 2 are both common, and mean the same.

3-6 are all grammatically correct, but the only way I'd say it is

she is wearing makeup (all finished)
she is putting on makeup (in the process)

use of the word "cosmetics" in such a context seems stilted to me.

The face is implied, and awkward if stated explicitly.