We've spent six months training him in the use of every security measure we know.

By now I had been well trained in its use.

Who trained his military forces in the use of it?

That's why thousands of us are trained in its use.

"And starting right now, you will train us in the use of the weapons systems."

"I know you were trained in the use of weapons."

She had been trained in the use of the instrument herself.

And we will even train your staff in the most efficient use of gas.

She is trained in the use of a long bow.

He had trained each in the use of the sword.