He is an expert programmer, and a very good spy.

He doesn't understand that that's why he's not a very good spy.

"With two of you, you'll make twice as good a spy."

He didn't understand any of our languages well enough to be a good spy for the Speaker.

Creatures of the air would make good spies for such a purpose.

"Ah, but a good spy always has a cover story."

He was much too nervous to be a very good spy.

Of course, it's always possible sufficiently good spies could have provided you with that information.

First, we need a good spy to keep us informed.

Every country has good spies and it is not always the biggest countries that have the most or the best.