`\color{aqua}{\text{#Cloudzy}}`

`1` What was the length of time since you last corresponded with your penpal `?`

`-` How long + have/has + not + S + V3/Vpp + O `?` : Đã bao lâu kể từ khi ai đó không làm gì `?`

`->` What was the length of time + since + S + last + V(quá khứ) + O `?` : Đã bao lâu rồi kể từ khi ai đó lần cuối làm gì .

`2` My boss suggested that I should shut down the computer on when I went out of the room .

`-` Gián tiếp gợi ý làm gì .

`@` S + suggested + that + S + (should) + V-inf + O .

`-` leave the computer on `><` shut the computer down : để máy bật `><` tắt máy .

`1)` What was the length of time since you last corresponded with your penpal?

`->` length of time: khoản thời gian

`->` How long have/has sb V3 = What was the length of time since sb V3: bao lâu kể từ khi ai làm gì

`2)` My boss suggested that I should shut the computer off when I went out of the room.

`->` suggest that sb do sth: gợi ý ai làm gì

`->` shut sth off: tắt cái gì (thường dùng cho máy tính, điện thoại, ... )

(Theo mình câu `1` làm là "When was the last time you corresponded with your penpal?" sẽ đúng nhất nhé)