$1. $ Delicious meals are often cooked for us by my mother

$→$ Câu bị động thì HTĐ : S + am/is/are + Vpp + (by O)

$→$ Dấu hiệu : often

$→$ Câu chủ động chia thì HTĐ thì câu bị động cũng vậy

$→$ Meals là số nhiều nên + are

$2. $ Emails are written to me twice a week by my close friend

$→$ Câu bị động thì HTĐ : S + am/is/are + Vpp + (by O)

$→$ Dấu hiệu : twice a week

$→$ Câu chủ động chia thì HTĐ thì câu bị động cũng vậy

$→$ Emails là số nhiều nên + are

$3. $ How is the environment often polluted by factories?

$→$ Câu bị động thì HTĐ : S + am/is/are + Vpp + (by O)

$→$ Dấu hiệu : often

$→$ Câu chủ động chia thì HTĐ thì câu bị động cũng vậy

$→$ The environment là số ít nên + is

$4. $ Her younger sister is not as beautiful as her

$→$ So sánh bằng : S + V + (not) + as + adj/adv + as + O

$5. $ They have studied English since 2010

$→$ S + began / started + to V/ V-ing + time ago

$→$ S + have/has + P2 / been Ving+ for / since ...

$→$ Since + Mốc thời gian

$@Re$

Trả lời:

1. My mother often cooks delicious meals for us. 

→ Delicious meals are often cooked for us by my mother.

2. My close friend writes emails to me twice a week.

→ Emails are written to me twice a week by my close friend.

3. How do factories often pollute the environment?

→ How is the environment often polluted by factories?

4. She is more beautiful than her younger sister.

→ Her sister is not beautiful than her.

5. They began studying English in 2010.

→ They have studied English since 2010.

Chúc bn hc tốt!!!

Nếu hay => vote 5* + ctrlhn!!!