Finding the case locked, he was obliged to force it, thus 63 betraying his presence. 
He betrayed his presence by forcing the locked case.
The case was unlocked but he stilled forced it.
Two girls are playing field hockey.
Yes, that is correct, I think they have nothing else.
The series is previewed by PBS.
It won't work.
People did not want to live where raiders could find them easily.
The art of papyrus-making was lost for a time in Egypt.