`50`.Tom has learnt English since 1990

`\rightarrow` Thì HTHT : S + have / has + V3 / PII ( `50 , 55 , 65` )

`\rightarrow` `DHNB` : since ( `50 , 51 , 59 , 60 , 62 , 65` )

`51`.He hasn't met my sister since last summer 

`\rightarrow` Thì HTHT ( PĐ ) : S + haven't / hasn't + V3 / PII ( `51 , 54 , 56 , 57 , 59 , 60 , 62 , 64` )

`52`.When did you start studying medicine ?

`\rightarrow` Thì QKĐ ( NV ) : Did + S + V ?

`\rightarrow` begin / start + V-ing / to V : Bắt đầu làm gì

`53`.The last time we came to the concert was a year ago

`\rightarrow` Thì QKĐ : S + Ved / V2

`\rightarrow` `DHNB` : ago

`54`.We haven't seen our grandfather for two years

`\rightarrow` `DHNB` : for ( `54 , 56 , 57 , 64` )

`55`.This is the first time I have ever read such a romantic story

`\rightarrow` `DHNB` : ever

`56`.My father hasn't seen my uncle for nearly twenty years

`57`.We haven't gone to a cinema for two years

`58`.It's over 20 years since he last came to his village

`\rightarrow` It is + time + since + S + last + Ved / V2 : Đã bao lâu kể từ khi ai đó lần cuối làm gì

`59`.We haven't seen him since Monday

`60`.I haven't seen David since 1989

`61`.When did they go to London ?

`\rightarrow` Thì QKĐ ( NV ) : Did + S + V ?

`\rightarrow` When dùng để hỏi về mốc thời gian

`62`.I haven't spoken to Jim since I sold him my old car

`63`.The last time I saw him was two weeks ago

`\rightarrow` The last time + S + Ved / V2 + was + time : Lần cuối làm gì

`64`.They haven't left their homeland for over two years

`65`.She has learnt English since 2003

`\text{# Kirigiri}`