He is famous _____the field of biology, but he is more known _____an environmentalist..
As soon as Charles had _____ a little from his surprise, his one thought was to get away.
He _____ the place where he had been bitten by an insect.
Trains stop here in order to _____ passengers only.
This album is _____ as it was the only one ever signed by the President.
In aerospace devices the weight of the necessary power producing equipment is _____.