It is crucial for a helmet to be worn by people whenever doing any dangerous sport.

1. (Hoặc có thể viết lại là: A helmet must be worn by people whenever doing any dangerous sport.)

People are always made to laugh by his jokes.

Job satisfaction is thought to be the most important by all employees.

He has the children looked after by his wife.

Let your room be cleaned!

1. (Hoặc có thể viết lại là: Your room should be cleaned!)