Question

这个英语句子是什么结构?

it's very necessary for us to learn from others,to draw experiences from others'successes.
其中to draw experiences from others'successes.在句中作什么成份啊,为什么中间要用逗号隔开.
"for us"在句中又作什么成份?

Answer 1

to draw experiences from others'successes.在句中也是作真正的主语。它和to learn from others是并列的。for us作to learn from others, to draw experiences from others' successes的逻辑主语。it是形式主语。
掌握句式：It is + 形容词 +(for sb.)+ 动词不定式（to do sth）就容易了。
解答满意吧。

Answer 2

It is + 形容词 +(for sb.)+ 动词不定式（to do sth）
做某事对某人而言怎么样
it是形式主语 后面的不定式才是真正的主语
，可以隔开两个并列的成分
这里的两个不定式是并列的主语
也可用and等并列连词来连接

Answer 3

it是形式主语，to learn from others, to draw experiences from others' successes是真正的主语。

Answer 4

it是形式主语，to learn from others, to draw experiences from others' successes是真正的主语。 这二者是并列的成份。for us表示to learn from others, to draw experiences from others' successes的动作逻辑主语