This is the 428th most frequent Czech word.
začal
"Začal" means "started" in English.
Here, 'začal' is used in the simple past tense to indicate the initiation of an action.
On začal číst knihu.
He started reading a book.
Here, 'začala' is the feminine past form linking the subject (a female teacher) to the commencement of an activity.
Učitelka začala hodinu otázkou.
The teacher began the lesson with a question.
In this sentence, 'začal' signifies the start of developing an interest, followed by a reflexive verb construction.