“Spent time for training” vs. “spent time on training” vs. “spent time on training of ”

Question

• We’ve spent X hours ?on training of the new employee.
• We’ve spent X hours ?on training the new employee.
• We’ve spent X hours ?for training the new employee.

Are these interchangeable?

Answer 1

With "spend," I normally follow these patterns:

spend something + on + Noun

spend something + V+ing 

So, I would correct all your sentences this way:

We've spent X hours on the training of the new employee.

We've spent X hours training the new employee.

I wouldn't use "for."

Answer 2

No, and you might as well simply say:

We've spent x hours training the new employee.