`8`. Mr. Nam last cooked when he was sick.
`->` S + last + V2/ed + when + S2 + V2/ed
`=` The last time Mr. Nam cooked was when he was sick.
`->` The last time + S + V2/ed + was + when + ....
`9`. We have studied English since we were too young.
`->` S + started + to V + when + S2 + V2/ed
`=` S + have/has + not + Vpp + since + S2 + V2/ed
`10`. It is 5 weeks since Tom and Alice (last) lived together.
`->` It + is + thời gian + since + S + (last) + V2/ed
`11`. It's the first time Duy has read this kind of story.
`->` S + have/has + not + Vpp + before
`=` It's the first time + S + have/has + Vpp