英语动词的三单形式有那些？

动词的第三人称单数形式（简称单三式）
1．一般在词尾加“-s”help-helps
make-makes
ride-rides
know-knows
2．在s
z
x
sh
ch
结尾的词在词尾加“-es”push-pushes
pass-passes
watch-watches
wash-washes
3．以“元音字母＋y”结尾时，加“-s”；以“辅音字母＋y”结尾时，变
y为i，再加“-es”play-plays
stay-stays
study-studies
carry-carries4．以“辅音字母＋o”结尾的词，多数在词尾加“-es”go-goes
do-does
5．be动词的单三式为is
6．have动词的单三式为has
(本文源自轻松英语行
http://englearn.zhan.cn.yahoo.com,转载请注明出处)
补充
:不定式的省略:
Wil
you
join
us?
你要同我们一道去吗？
I
should
love
to
(join
you).
我愿意。
The
boy
wanted
to
ride
his
bicycle
in
the
street
but
his
mother
told
him
not
to.那个男孩想要到街道上骑自行车，但是他的妈妈叫他不要去。
Alice,
why
didn't
you
come
yesterday?
爱丽斯，你昨天为什么没来？
I
was
going
to,
but
I
had
an
unexpected
visitor.
我本来是要来的，但是家里突然来了一个客人。