2. A new kind of plants have just beenproduced.

→ câu bị động thì HTHT: S + have/has + been + V3/ed +(by+O)

3. They asked him what he would do to help his mother.

→ câu tường thuật dạng câu hỏi Wh/H: S + asked + O + Wh/H + S +V(lùi thì) ( lùi từ 'will' → 'would' )

4. They have played tennis since 2003.

→ S + started/bagan + to_V/V_ing + S + time: Lần đầu làm gì

    S + have/has + V3/ed + for + khoảng thời gian

                                          + since + mốc thời gian

VI.

1. Nam said he would go to Ha Noi the following day.

2. That house was built in 1975.

3. Two days ago, I decided to visit Nha Trang.

4. I wanted to get the fresh air, so I wnt to the garden.

@ $quynhly$

2. A new kind of plants has just been produced.

3. They asked him what he would do to help his mother.

4. They have played tennis since 2003

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1. Nam said he would go to Ha Noi the following day.

2. That house was built in 1975

3. Two days ago, I decided to visit Nha Trang

4. I wanted to get fresh air so I went to the garden.