`1`.We have never met before

`\rightarrow` Thì HTHT : S + have / has + never + VpII + before : Chưa từng làm gì trước kia

`2`.Because his leg was bad , he walked slowly

`\rightarrow` Because + C1 + C2 : Bởi vì

`\rightarrow` Dùng để chỉ nguyên nhân , lý do

`3`.The children are excited about opening their presents

`\rightarrow` be excited about + V-ing : Hứng thú làm gì

`4`.Our teacher said that trash shouldn't be thrown onto the water so as to keep the water clean

`\rightarrow` Tường thuật : S + said + that + S + V ( lùi thì )

`\rightarrow` Should `->` Should ( Không thể lùi thêm )

`\rightarrow` BĐ `-` Should : S + should be + VpII ( by O )

`\text{@ Tails347}`

`1`. `->` We have never met before

`+)`Thì Hiện tại hoàn thành-ever;never

`+)`It is the first time `+` `HTHT( S+has`/`have+PII)` : đây là lần đầu tiên...

≈ Never+PII+ before: chưa bao giờ... trước đây

`2.``->` Because his leg was bad, he walked slowly.

`+)` because: bởi vì

`+)` Because + clause (S+V) 

    ≈  Because of+ Ving/ N

`+)` Quá khứ đơn - walked

`->` tobe- chia was/were

`3.``->`The children are excited about opening their presents

Looking forward to doing st : mong chờ điều gì.

≈tobe excited about doing st : háo hức, mong chờ điều gì

`4.` `->` Our teacher said that trash should be not thrown onto the water so as to keep the water clean.

+)Câu trực-> gián tiếp : S+ said( to sb)/ told ( sb) +(that) + clause ( lùi thì)

Lùi thì : should : giữ nguyên 

+) câu bị động : S+ should be+PII