—Is that Tom in the teachers' office?--No, it ________ be him. He's gone to the hospital.
—It’s Father’s Day today,________?—Yes.Let’s buy a gift for Dad.
Here ________ four ________ of my family.
Everyone m our class ________ here.
—There is too much rain in many parts of the world now.—That sounds ________.
The food safety is a serious ________ in our country.We should try to solve it.