He came to see his uncle _______ a snowy day.[ ]

Billy: I’ve been fixing the computer for over three hours, but it still doesn’t work. Nana: Why don’t you take a rest and try ? Maybe you’ll do better then.

What’s the matter _____ the kitchen fan? [ ]

The 2014 Summer Youth Olympic Games will be heldAugust 2014 in Nanjing . [ ]

The woman _____ a baby begs from door to door every day.[ ]