句子改被动态~``1.This school allows students to design their own u

1.This school allows students to design their own uniforms.
Students are allowed to design their own uniforms by this school.
2.He allowed his son to watch TV for half an hour yesterday.
His son was allowed to watch TV for half an hour yesterday by him.
被动态的句子该怎么转换?
举个例子来说：
主动：Sb. do/does sth.
被动：Sth. be(is/are) done by sb.

Students are allowed to design their own uniforms.
His son was allowed to watch TV for half an hour yesterday.

1.Students are allowed to design their own uniforms by this school.
2.His son was allowed to watch TV for half an hour yesterday by him.