What do you often do at weekend?
→ What is often done by you at weekend?
*Question word + is/ am/ are + PP + (by O)?
*Bonus:
QKĐ: S + was/ were + PP + (by O)
HTĐ: S + am/ is/ are + PP + (by O)
HTTD: S + am/ is/ are + being + PP + (by O)
HTHT: S + have/ has + been + PP+ (by O)
TLĐ: S + will be + PP + (by O)
TLG: S + is/ am/ are + going to + be + PP + (by O)
S + modal verb (should, must, have to, can,...) + be + PP + (by O)
