blackboard 拆开背， black表示黑，board表示木板

blackboard：n.黑板，复数： blackboards

例句：

There was a blackboard with seven names chalked on it.

黑板上用粉笔写着7个人名。

He chalked the message on the blackboard

他用粉笔将消息写在黑板上。

The teacher wrote on the blackboard with a piece of chalk.

老师用粉笔在黑板上写字。

Look at the blackboard.

看黑板。

Can you see the words on the blackboard clearly?

黑板上的字你看得真吗？