the homeless children will be taken care of by another five volunteers this week 为什么要加 of额 不是有一个by做介

题目

the homeless children will be taken care of by another five volunteers this week 为什么要加 of额 不是有一个by做介词 有介宾了吗
the houses here are to be pulled down for a new supermarket为什么有个to 额

答案

take care of是一个词组,of在整句句子中不作介词看待
这里的to意思为将要