With prices （）so much, it is difficult for the school to plan a budget.

Many types of rock are （）from volcanoes as solid, fragm...

单项选择题Many types of rock are （）from volcanoes as solid, fragmentary material.

He raised his eyebrows and stuck his head forward and （...

单项选择题He raised his eyebrows and stuck his head forward and （）it in a single nod, a gesture boys used then for O. K. when they were pleased.

The ball （）two or three times before rolling down the s...

单项选择题The ball （）two or three times before rolling down the slope.