She is merely testing the system; the triggers are automatic.

Or was he merely testing the waters, as it were, to see whether a romance between them was possible?

They assumed he was merely testing the waters, to see how much he could get.

Or merely testing him, as a horse will test any new, uncertain rider?

I was merely testing the strength of the door.

Thus far, his actions had no name except it, and he merely tested the possibilities.

It merely tests how long certain 'typical' graphics tasks take to execute.

He seemed to imply that the other two knew the translation all along, were merely testing him.

The multiple-choice system merely tests their ability to find the most reasonable choice.

They were not merely testing our preparedness in that part of space, but seeing whether we would call them on it.