It is one thing to know that a man is guilty, it is quite another matter to prove him so. 
There is a difference between knowing a man is guilty and proving him guilty.
It is easy to prove that a man is guilty if you already know that he is.
The dog is black.
It's pretty understandable.
Workers painting signs.
A woman is inside on her phone
The man and woman sit together at the reception.
A mother holds her newborn.