To find out definitely I shall have to make certain experiments.

One day I got a new man, and told him to conduct a certain experiment.

For certain experiments, female flies were used, as indicated.

It looked as though the owner had started certain experiments, then discarded them.

She would bring me, along with other news, the result of a certain experiment which I had been starting.

We can get some idea from certain experiments that have been done with rats.

I am much interested in certain experiments with the kite, which would be, if not a pleasure, at least a novel experience to you.

All I ask of you is to perform a certain scientific experiment.

Space is a better place to do certain experiments.

Comrade, there's a certain experiment I would like to try.