Both yes—no questions and interrogative-word (wh) questions provide for collapsing two or more interrogative sentences into a single sentence by other means than unreduced conjunction: Were you there and did you see what happened? (unreduced) Were you there and saw what happened? (reduced) Did they come early and did they get a seat? (unreduced) Did they come early and got a seat? (reduced) Who ate and what did he eat? (unreduced) Who ate what? (reduced)