be needed to do与need to be done

e needed to do=be needed in order to do这个不定式是目的状语
如：
A lot of time is needed to do this work.
(为了）做这项工作,需要很多时间.
=A lot of time is needed in order to do this work.
need to be done=need doing
需要被做
如：
The watch needs repairing=The watch needs to be repaired.
但如果有执行者,就只能用to be done
如：
The watch needs to be repaired by the man.

be needed to do意思被需要用来做。。。它的主动形式相当于people need...to do
need to be done需要被。。。如:The watch needs to be repaird.这块表需要修理。它等于The watch needs repairing.

1是被动啊被需要2是需要，就那么简单啊
eg it is needed to work
it need to work。不能to be work。2后面的动词要看情况用被动

sth/sb be needed to do sth
需要某人或某物来做什么事 比如 A knif is needed to kill this dog. 杀狗要用这把刀，强调的是主体在做事情中的必不可少的地位。
be needed to do 的用法可以类似于be used to do(被用于)
need to be done是指要做某事
my hair nee...

She is needed to do the work.
她被需要去做那份工作。
be needed to do前面加的是要做这件事的主语，后面是要做的事
The work need to be done.
那份工作需要被做。
need to be done前面加的是要被做的事情