老师在黑板上写字。
lǎoshī zài hēibǎn shàng xiězì 。
The teacher is writing on the blackboard.
请把课本放在黑板旁边。
qǐng bǎ kèběn fàngzài hēibǎn pángbiān 。
Please put the textbook next to the blackboard.
黑板是教室里的重要工具。
hēibǎn shì jiàoshì lǐ de zhòngyào gōngjù 。
The blackboard is an important tool in the classroom.