It was too cold and windy , so we could see ____ people walking in the street .

Are Mr. and Mrs. Wang living alone in the house? —Yes, they have three sons, but ______ of them live in their own houses.

_____? As far as I know, he never came late to class.

Green is the color of _______ nature. And you can enjoy the colorful rainbow in _______ sky after the rain.

He used to up late,but now he gets used toup early .