Brognola killed the engine and spent a moment feeling for his weapons, making doubly certain that they would be there when he required them.

In the present crisis this was doubly certain.

Narvo was dawdling around to make doubly certain he was under no scrutiny before he proceeded to his real goal.

However, to make doubly certain, he sprayed on a second layer; then he set off toward the antenna.

Of course, she mentioned the prince to make doubly certain of her victory over me.

A fact, she was grimly aware, that made their deaths doubly certain if Kaen should prevail in what was coming.

It might be a good idea to make doubly certain just who had died.

If I want to make doubly certain, I choose three other stars and try again.

It took Scott a moment to comprehend-then a long, sharp look at Kirk's expression to make doubly certain.

Decker would have made doubly certain of all that by now, anyway.