Aslam is believed ________________ this window.
Aslam is believed ________________ this window.
Explanation
Aslam is believed to have broken this window means مانا جاتا ہیکہ یہ کھڑکی اسلم توڑ چکا ہے
This is a sentence of Passive Voice.
Break an irregular verb here.
Broke is the second and broken is the third form of Break.