Question

求英语句子成分分析？

He is walking accross the grass
He是主语
is walking是谓语
accross the grass是宾语
对么??

Answer 1

不对。across the grass穿过草地，是介词短语。介词短语是不可能作宾语旳。只有名词，代词，数词，不定式，动名词，句子可以。

追问

那这个句子成分是?

Answer 2

这句是主语从句。
What
it
was
to
become
主语
was
谓语
uncertain
形容词当表语
until
between
4.5and3.8billion
years
ago
。until在这里是介词，between
4.5and3.8billion
years
ago
是介词宾语。这句是构成整句时间状语。
when
the
dust
settled
into
a
solid
globe。是由when引导的定语从句，先行词是between
4.5and3.8billion
years
ago
例句；he
came
last
night
when
i
was
out.