何必的英文：
there is no need
why should

参考例句：

There was no need for you to fight against your own men.
你何必同室操戈。

Why should you be so suspicious?
你何必多疑?

Yo, what's with all this hostility?
喂，何必这么凶？

An unnecessary reference to his criminal past
何必提到他的前科.

Why try to dredge up the sad facts of the past?
过去的伤心事何必重提呢？

Why keep a dog and bark yourself?
养狗何必自吠？

Why use wood when you can use plastic?
既然能用塑料，何必非用木料？

I will not keep a dog and Bark myself
既然养了狗,何必自己叫

You can't be dogmatic in matters of taste.
对于个人爱好的事,何必这样自以为是.

You can' t be dogmatic in matters of taste
对於个人爱好的事,何必这样自以为是

there是什么意思：
adv.在那里；在那点上
int. 你瞧，好啦
pron. 表示某物或某人的存在或某事的发生
need是什么意思：
v. 需要
n. 需要，必要；需要的东西；需求

We need to provide for everything we will need for the trip.
我们必须准备所有旅行要用的东西。

You need money and time, in addition, you need diligence.
你需要金钱和时间，此外你还需要努力。

Do you need to wee?
你要撒尿吗？

why是什么意思：
adv. （用作疑问副词）为什么，（用做关系副词）为什么
n. 原因，理由
int. 咦，哎呀，哦，当然，唔

Why are you in such a hurry?
你为什么这样急呢?

Is this why the Yen is so strong?
这是日元如此强劲的原因吗？

Why, I was fast asleep.
怎么，我睡得很熟的呀。