This is the 13829th most frequent German word.
erschrecken
To frighten or be frightened.
In this context, 'erschreckte' is used as the past tense of the verb 'erschrecken', meaning 'to startle or scare'. The sentence illustrates causing someone else to feel startled or scared.
Er erschreckte mich mit seinem plötzlichen Auftauchen.
He startled me with his sudden appearance.
Here, 'erschrak' is in the past tense of the intransitive usage, 'sich erschrecken', which indicates the subject themselves felt startled or scared.
Ich erschrak, als ich das laute Geräusch hörte.
I got startled when I heard the loud noise.
In this sentence, 'erschreckte' is used as the past tense of the transitive verb, showing that the book caused him to feel fear or suspense.