在黑板上写字怎么用英语说?

老师正在在黑板上写字。：The teacher is writing on the blackboard.
在黑板上写字：write on the blackboard
老师正在黑板前面写字。也许是刚才那句；如果没写黑板上，就是：The teacher is writing in front of the blackboard.

1、“在黑板上写字”的英语翻译：Writing on the blackboard
2、举例：
老师正在黑板前面写字
Teachers are in front of the blackboard writing

老师正在黑板前面写字用英语说，
Teacher is writing on the blackboard

老师正在黑板前面写字
Teachers are in front of the blackboard writing

Writing on the blackboard