$\text{1. A new stadium was being built }$

$\text{- Cấu trúc câu bị động quá khứ tiếp diễn:}$

$\text{S+ was/were + being + Vpp/ed+ (by+ O)}$

$\text{2. America was discovered by Columbus in 1992 }$

$\text{- Cấu trúc bị động quá khứ đơn: }$

$\text{S+was/were+ Vpp/ed+ (by+O )}$

$\text{3. The classroom is being cleaned at the moment  }$

$\text{- Cấu trúc bị động hiện tại tiếp diễn: }$

$\text{S+ am/is/are + being + Vpp/ed+ (by+O)}$

$\text{4. Thousands of home have been destroyed by the lava}$

$\text{- Cấu trúc bị động hiện tại hoàn thành:}$

$\text{S+ have/has+ been+ Vpp/ed+ (by+O)}$

$\text{5. The Earth's climate will be affected by the vocano }$

$\text{- Cấu trúc bị động tương lai đơn:}$

$\text{S+ will be+ Vpp/ed+ (by+ O)}$

Was build by them

Vì:

Mà stadium là số ít

-> S + was + V1 + by + S

Was discoverd by Columbus

Vì:

Mà America là số ít

-> S + was + V1 + by + S

The classroom was clean by someone

Vì:

Mà classroom là số ít

-> S + was + V1 + by + S

Thousands of home were destroyed by the lava

Vì:

Mà Thousands là số nhiều

-> S + were + V1 + by + S

The earths climate will affect by the volcano

Vì:

Ta có will là thì tương lai

-> S + will + V1 + by + S