$1$. When did Rob go swimming last year?
$2$. Where were the children yesterday year?
$3$. Why should people exercise?
$4$. What did you do last night?
$5$. How long have we lived in Quy Nhon city?
$6$. How many exams has she had so far this month?
$7$. Have you been in Singapore twice?
$8$. How many people has Seoul a population of?