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That's before a professional nanny arrives unannounced at the door.

Several days later a group of officers and civilians from Washington arrived unannounced.

I must say, my lord, you weren't nice to arrive unannounced.

On the other hand, there were advantages to arriving unannounced.

As you know, it is my custom to arrive unannounced.

They had arrived unannounced, looking concerned and out of sorts.

You arriving completely unannounced in the middle of the night, using our house as a hotel.

He'd drive over to the Grove tonight and arrive unannounced.

"No friends either, to arrive unannounced under cover of darkness."

Officials arrived unannounced and pulled selected American students out for drug testing.