have got to是have to的口头说法，意思是“不得不”。如：
I have got to go now.(缩写成：I've got to go now.)
一楼和二楼的例子也是正确的，但这两例中的have got to不是一个固定短语。
第一例的get是系动词，意思是“变得”，get to do sth.变得做某事了。I have got to know the meaning of this word at last.意思是“我（原先不知道这个单词的意思，）现在终于（变得）知道了”。
第二例中的get是“到达”的意思。

They have got to abide by the rules.
他们必须要遵守规定。
《柯林斯英汉双解大词典》
There is no beating about the bush, for we know quite well what it was, and have got to tell.
没有必要拐弯抹角，因为我们很清楚那是什么，必须讲出来。
精选例句
I think, typically, the majority of people's experience is that you have got to claw your way through it.
我认为，一般来说，大多数人的经验是你必须设法通过它。
精选例句
The decision has been made and I have got to stand by it.
这个决定已经作出，我得坚持它。
《柯林斯英汉双解大词典》
You have got to buck up on certain situations and create your own destiny, which is up to each and every one of us.
在一些特定环境下，你要振作精神，创造属于你自己的命运，这对我们每个人都是受用的。
精选例句
As they often play football together, they have got to know each other quite well.
他们常在一起踢足球，一来二去地也就熟了。
《新英汉大辞典》
But if it wants to realise its dream, Vietnam must learn the right lessons from its own story so far, and from those neighbours who have got to where it wants to be.
但是要实现它的梦想，越南必须从他本国至今的历史和那些已经实现越南梦寐以求的目标的邻国身上汲取经验。
www.ecocn.org
So we have got to create in this world also institutions for peacekeeping and humanitarian aid, but also for reconstruction and security for some www.souquanme.comof the conflict-ridden states of the world.
因此我们必须在这个世界建立起用以维和以及人道救援的机构，还有帮助那些危难中的国家重建和安全的机构。

I have got to get up early.(我不得不起早）
I have got to borrow books for my little sister.（我不得不为我的小妹妹借书）
I have got to read the story for my younger brother.（我不得不为我弟弟读故事）

But you have golvIbxlfgQkt to calm down.
但是你必须要冷静下来。
（望采纳~）