"I always be with you"这句话有语法错误吗？

有语法错误。be动词搭配错误。
改正：I'm always with you. 现在一般时，两层表义：我总是支持你。或我总是陪伴在你左右。
亦可使用过去一般时，如：I was always with you, but you made me disappointed again and again.

有，要改为：
I am always with you.
或 I will always be with you.

i will always be with you

没错！

应该改成
i will always be with you.
加歌wil

I will always be with you.
这个比较恰当

有，be是原型。句子没时态。
可以改成 I am always with you.
或者I will always be with you.