完成句子，为什么用 so as to be received in time,考的是什么知识点，要详细解答

Question

All the food and clothes must be sent immediately ________________ ( 以便及时收到) by the people there. (so receive )

Answer 1

All the food and clothes must be sent immediately, so that they can be received in time by the people there.
①all the +名词 所有的这些.......all the children所有的这些孩子all the pears所有的这些梨
②情态动词的被动语态 情态动词（should、must、can、may等）+be+过去分词
③so that +句子 为的是，以便于.......
④in time及时 on time 按时

Answer 2

so as to do sth.和so as to be done表示某事的结果。前面是不定式的主动形式，后面是不定式的被动形式。
这句话可以转换成结果状语从句：
All the food and clothes must be sent immediately, so that they can be received in time by the people there.