Giúp mình với ạ!!!!!!! 39. This ladder is high. You can use it to hang Christmas decorations.  This ladder is ___________________________________________________________. 41. She started learning English since she was in grade 4.  She has ________________________________________________________________. 44. He began collecting stamps in 2001.  He has __________________________________________________________________. 45. When did you first know that teacher?  How long have ___________________________________________________________?

`39`.This ladder is high enough for you to use it to hang Christmas decorations

`\rightarrow` Enough : S + be / be not + adj + enough ( for O ) + to V

`41`.She has learned English since she was in grade 4

`\rightarrow` Thì HTHT : S + have / has + V3 / PII

`\rightarrow` Đặc điểm nhận dạng : since

`44`.He has collected stamps since 2001

`\rightarrow` Thì HTHT : S + have / has + V3 / PII

`\rightarrow` Đặc điểm nhận dạng : since

`45`.How long have you first known that teacher ?

`\rightarrow` Thì HTHT ( CNV ) : Have / Has + S + V3 / PII ?

`\text{@ TheFox}`