----Look at the boy running on the playground. Is it David?---- It ______ be him. I saw him go to the teachers’ office just now.
-----It’s hot. Would you mind my _____ the window? ------ _____.Do it as you like, please!
— Kitty, do you know ______? — Sure, about forty minutes.
I walk ______ the square after supper every day, so I know very well every small shop there.
Do you know the man_______ saved five people in the fire?
The old man was so_______ the good news that he couldn’t say a word.