blackboard是可数名词吗

blackboard用法例句

1、There was a blackboard with seven names chalked on it.

黑板上用粉笔写着7个人名。

2、Teaching off a blackboard is boring, and undoubtedly turns people off.

照本宣科枯燥乏味，无疑会使人们丧失学习兴趣。

3、With a stick of chalk he wrote her order on a blackboard.

他用一截粉笔将她的指示写在黑板上。