The stolen watch was found. (make it complex)

• Subject এরপরের verb টি past particle form এ থাকলে Simple sentence কে Complex sentence করার নিয়ম:
- Subject বসে।
- Relative pronoun (who,which,that) বসে।
- Tense অনুযায়ী auxiliary verb বসে।
- প্রদত্ত past participle থেকে sentence -এর বাকি অংশ।

Simple: The stolen watch was found.
Complex: The watch that was stolen was found.

Source: Advanced Learner's Communicative English Grammar & Composition By Chowdhury & Hossain.