They were probably just testing to see if anyone was home.

They test the system to see if it is fast and private.

"You must test me to see whether I am able to reach a higher state of consciousness."

"Then we test to see whether those procedures are being followed."

The sea tests them to see if they have learned from their lives.

Later, add them back one at a time, testing to see if they cause trouble.

Now what we are trying to do in conversation is to test the changes to see if they make sense.

"We test to see that no one on our teams is using it."

So, where can I test this to see if it actually works?

So we must test to see whether the device works.