大家不都是否定词吗？是否还有其他类似例子？

比如：

I never liked him. （正确）

He never help me. （错误）

He never helps me. （正确）

He never helped me. （正确）

He has never helped me. （正确）

A good man never cheats. （正确）

我从未爱过他。

1. I have never liked/loved him.

2. I haven't (=have not)  liked/loved him.

3. I never liked/loved him.

  4. I never like / love him. （我从来不爱他。）

never和not都是副词,按理说功能差不多,区别在于习惯用法吧.

在有情态动词或者be动词的句子里, never也不能不和情态动词或be动词连用.

比如I can fly. 否定句写成i never fly. 就不对了.

I am old否定句写成I never old也是不对的.

在仅有实义动词的句子里,never不用加助动词,而not加助动词我理解为"增加助动词起强调作用的习惯用法. 毕竟not和助动词连用有专门的缩写.