` 1. ` I haven't seen him since ` 1998 `

` - ` S + last + V ( 2 / ed ) + sb + time: Lần cuối ai đó gặp ai là khi nào

` - ` ` = ` S + haven't + V ( 3 / ed ) + sb + time: Ai đó chưa gặp ai

` - ` HTHT: ` ( - ) ` S + have / has + not + V ( 3 / ed ) + O

` - ` Since + mốc thời gian

` 2. ` Getting into work this morning was a bit difficult

` - ` It + tobe + adj + ( for sb ) + to V: Nó như thế nào cho ai đó làm gì

` - ` ` = ` V - ing + tobe + adj: Làm gì đó là như thế nào

` - ` V - ing đứng đầu làm chủ ngữ

` 3. ` It's difficult to train dogs

` - ` It + tobe + adj + ( for sb ) + to V: Nó như thế nào cho ai đó làm gì

` - ` ` = ` S + tobe + adj + to V

` # ` ` Ka `

`1.` I haven't seen him since 1998.

`-` S+ last+ V(ed/v2)+O+...

`<=>` S+ haven't/hasn't+ V(ed/v3)+O+since/for+...

`2.` Getting to work this morning was a bit difficult for me

`-` It+ tobe+ adj+ to_V+....

`<=>` V-ing+...+tobe+ adj+ for One's

`@` QKĐ với tobe: S+ was/were+N/adj

`3.` It is difficult to train dogs

`-` S+ tobe+ adj+to_V

`<=>` It +tobe+ adj+ to_V+S

`@`HTĐ với tobe: S+ am/is/are+N/adj

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