Mary heard ____strange sound at ____midnight outside her house and got scared.
I don't doubt ______ he will pass the tomorrow’s exam.
We were ______ on our way to the airport because of the heavy snow.
______ all the required papers, he didn’t answer the questions fluently in class.
When he reached the final line,everyone_____laughing.
The two elderly sisters, ____ so long, held each other.