Of the equipment we have produced, this sells best, for it has the advantage over ________ of working efficiently.     

Whenever I met him, ____ was fairly often, I like his sweet and hopeful smile.

______ would have been too embarrassed, but he walked right up and asked for her autograph.

To save class time, our teacher has ________ students do half of the exercise in class and complete the other half for homework. .

Seeing a large crowd at the street corner，I became aware of     unusual happening．