It ______ we know the result of the experiment.
All the donated money should be made full use ___the homeless people Ya'an city of Sichuan province.
.Who is knocking at the door? ——It ______ Mr. Black, because he_______Washington.
It’s raining heavily .But ___ of the farmers are picking up the apples ___ the trees.
I often see her _the room. I saw her _the room again just now.
He has __________ for an hour .