The boys often used to throw a stone or two at the glasshouse because（）

单项选择题Mr. Flowers had no way to prevent harm to his glasshouse because （）

A．he was too old to see who did it
B．the boys ran too fast for him to catch
C．it was impossible for him to be on guard all the time
D．he was too kind to beat the boys

单项选择题The boys threw stones at Mr. Flowers' notice because（）

A．they wanted to do what they were told not to do
B．the notice was closer to the path
C．they hated to see the notice
D．the notice was in the way