It is human nature to think back to a golden age _____ one’s country was strong and respected[ ]

There is a crowd of people in front of the house over thereWhat do you suppose _____ there?

Imperfect goods are ________ by our quality control center in case they come into the consuming of the customers.[ ]

下列各句中，没有语病的一句是（    ）

Do you mind if I open the window— .