Beijing was attacked by such a terrible sandstorm ______few citizens had ever experienced before.
The reason _____ he could not go there was _____ his grades were too low.
________students are playing on the playground. ______students there is at least over 100.
It was in the park_____the lost bike was spotted yesterday.
He is so fat that he has decided to______.
Do you know the tall girl_____in red?