1. People grow rice in tropical countries.

=>Rice is grown in tropical countries(by people).

2. Viet Nam exports a lot of rice to China.

=>A lot of rice is exported to China by Viet Nam.

3. They built that bridge many years ago.

=>That bridge was built many years ago (by them).

4. Peter invited me to his party 2 days ago.

=>I was invited by Peter to his party 2 days ago.

5. I met him at the airport last week.

=>He was met at the airport last week (by me).

Chúc bạn học tốt!

$\text{1. People grow rice in tropical countries.}$

$\text{→ Rice are grown in tropical countries.}$

$\text{2. Viet Nam exports a lot of rice to China.}$

$\text{→ A lot of rice are exported to China by Viet Nam}$

$\text{3. They built that bridge many years ago.}$

$\text{→ That bridge was built many years ago.}$

$\text{4. Peter invited me to his party 2 days ago.}$

$\text{→ I were invited to his party by Peter 2 days ago.}$

$\text{5. I met him at the airport last week.}$

$\text{→ He was met at the airport last week.}$