In recent years________global warming is becoming ________ concern for people all over the world.
Great changes ___________in my hometown in the past 30 years.
The students went into the classroom,________.
As Mary ______ a poem, her little sister ______ asleep.
The workers ______ a new restaurant. It is said that the construction work will be finished next month.
When ____ about the possibility that Justin was taken away by aliens, Detective San Peterson, who has taken charge of the case, didn’t say much.