How to use "effective" in a sentence

If I read the temper of our people correctly, we now realize, as we have never realized before, our interdependence on each other; that we cannot merely take, but we must give as well; that if we are to go forward, we must move as a trained and loyal army willing to sacrifice for the good of a common discipline, because without such discipline no progress can be made, no leadership becomes effective.

"They're effective and reliable," said Bob.

The silencer was so effective that the shots could not be heard above the brittle, papery rustle of the wind.

Tamaguchi drove us very hard until we isolated the antibody and figured out why it was so effective against the disease

They were never able to find an antibody or an antibiotic that was effective against it