Mary often goes home as soon as the class is over. She doesn't want her mother to wait for her.
`=>` Mary often goes home as soon as the class is over in order not to let her mother wait for her.
`=` Mary often goes home as soon as the class is over so as not to let her mother wait for her.
* Cấu trúc: so as not to + Vinf: để mà (phủ định)
in order not to + Vinf: để mà (phủ định)
let + SO + Vinf: cho phép