--Have you seen Jack? His mother is looking for him all the afternoon.--No, I haven’t. I am sure her mother________be very worried.
Don’t swim here, or you may be ____ .
— What will the weather be like tomorrow? — It might be ____ .
I was watching TV ____ the thief came into the house.
Look! The boy is sitting ____ a tree.
— ____ you reading at this time yesterday? — No, I was ____ .