The boys playing are my friends.这句话对吗?

Question

这个句子实际上完整的或许是 The boys who are playing are my friends. 我把关系代词和系动词省略,这个句型对吗? 另外,老师以前说过用ed修饰主语,那又是 怎么回事? 什么时候用ING,什么时候用ed,哪为高人详细指点,不胜感激.

Answer 1

The
boys
playing
are
my
friends.
是正确的,可以把中间的(who)和（be）动词省略
例如：The
little
boy
standing
over
there
is
a
classmate
of
mine.
站在那边的小男孩是我班的同学。
什么时候用ING,什么时候用ed，是要依照你
完整的句子
中出现的格式。
给你一个复杂一些的例子：
The
houses
being
built
are
for
the
teachers.
=
The
houses（which/that
are）being
built
are
for
the
teachers.
这里没有省略
Be动词
是应为
被动语态
三种时态的:
The
problem
to
be
discussed
tomorrow
is
very
important
.
The
problem
discussed
yesterday
is
very
important.
The
problem
being
discussed
now
is
very
important.
强调一下,在省略之后就不是
定语从句
了,而是
非谓语动词
作定语.

Answer 2

这句话不对应该是
The
boys
are
playing
with
my
friends.
ed
表示被动，或动作已完成；而ing表示主动，或动作进行。

Answer 3

同意楼上，做主语是不能省who
are
或者The
playing
boys
are
my
friends.
分词做修饰名词时放在前，短语放在后。