I had to buy ________ these books because I didn't know which one was the best.

 Do you really believe that Mr White has blamed us for the accident,especially ________ ?

___ knows the way to the hospital so we have to ask the policeman for help.

To save class time, our teacher has ______students do half of the exercises in class and complete the other half for homework.

I wanted to buy a storybook but there were______ left in that bookstore．