able
to
與can區別：
be
able
to
和
can都是能夠做某事，意思壹樣，以下是兩者用法區別：
(1)
be
able
to
強調通過努力而獲得的能力，而can則強調自身已具有的能力。如：
She
can
sing
the
song
in
English.
她能用英語唱這首歌。
He
will
be
able
to
sing
this
song
in
English
in
a
few
minutes,
too.
幾小時之後，他也能用英語唱這首歌。
(2)
be
able
to
強調壹種結果，而can只強調壹種可能。如：
Luckily,
he
was
able
to
escape
from
the
big
fire
in
the
end.
幸運的是，他終於逃出了大火。
If
he
got
here
a
few
hours
earlier,
I
could
save
him.
要是他早幾小時來，我還能救他。
(3)
be
able
to
可以有各種時態；而can只有壹般現在和壹般過去兩種時態。如：
I
could
help
you
last
night,
but
you
didn’t
come.
昨天晚上我能幫妳，而妳又沒來。
Can
you
see
it
there?
妳能看見它在那兒嗎？
He
is
/
was
/
will
be
able
to
help
you.
他能幫妳的忙(from
www.yygrammar.com)。
(4)
can可用於表示可能性，推測，允許等情況，而be
able
to通常不這樣用。