Questions & Answers about המורה כתבה כותרת חדשה על הלוח.
כתבה is the past tense, 3rd person singular feminine form of כתב (to write).
So this tells you that the subject is understood as feminine singular:
- המורה כתבה = the teacher (female) wrote
- המורה כתב = the teacher (male) wrote
In Hebrew, the verb often shows gender in the past tense.
Not by itself, necessarily. מורה can refer to a teacher of either sex in many contexts.
What makes it clearly female here is the verb כתבה. The verb agrees with the teacher, so we know the sentence means the female teacher wrote.
If it were a male teacher, the sentence would be:
- המורה כתב כותרת חדשה על הלוח.