Diethyl sulfate is a useful ethylating agent in organic synthesis.

No one knows how useful biological agents or "bugs" would be on the battlefield.

There's a real lack of understanding here of how useful and important an agent can be.

Perhaps it is something of a gamble," Radan admitted, "but he is a useful agent.

Several useful agents have been found in unexpected places.

Some drugs are useful agents in the treatment of disease in man and animals but some may also produce undesirable effects.

And yet, what a nice thing for Russia to be able to afford such a luxury as long-serving, minimally useful secret agents.

Originally, he had seemed a useful agent for the collection of small holdings, but Tippin might now have his sights set on larger trans- actions.

Moe Shrevnitz was one of The Shadow's most secret and useful agents.

Then other potentially useful agents, the ex-military, and teachers, will be examined.