-We had _______really smoggy December this year.-I can’t remember _____ winter when air was polluted so severely.
____ under the tree was a charming girl aged about seventeen and eighteen.
_____ the city’s public school system should be open to the children of migrant workers has become the focus of discussion.
On seeing_____ gift they wanted, the kids screamed with _____ delight.
—I just can't stop worrying about the result of my medical examination.—__.There’s nothing you can do now but wait.
The real secret to successful learning lies in students____an interest in what they are doing.