`29`. This is the first time they have had such a cold winter.
`<=>` It is the coldest winter they have ever had.
`->` This is the first time + S + have/ has + V2
`<=>` S +have/ has + never + V2 + before
`<=>` This is (It is) the most + Adj/ Adj + est + N + S + have/ has ever + V2
`30.` It is the first time I have met such a famous person.
`<=>` This is the most famous person I have ever met.
`->` Tương tự câu `29`
`31.` It's a long time since I last saw him.
`->` The last time + S + V2 + was + khoảng thời gian + ago
`<=>` S + last + V2 + khoảng thời gian + ago
`<=>` S + have/ has + not = haven't/ hasn't + V2 + for + khoảng thời gian
`<=>` It + is + khoảng thời gian + since + S + V2
`32.` We statered to learn English four years ago.
`->` S + have + V2/ have been + for + khoảng thời gian
`<=>` S + started + V-ing/ to V + khoảng thời gian + ago
`33.` This is the worst cold I have ever had.
`->` Tương tự câu `29`
