✨ ベストアンサー ✨
1) What sports did you play?
2) I don't know how old she is.
※I(S1) don't know(V1) <how old she(S2) is(V2)>(O1).
3) Do you know who won the Nobel Prize for Peace?
※Do you(S1) know(V1) <who(S2) won(V2) the Nobel Prize for Peace(O2)>(O1)?
参考にしてください。