1. I have no one to help me.

2. I have no one who will help me.
3. I have no one who should help me.
4. I have no one who can help me.
5. I have no one wh has to help me.

Does #1 mean #2, #3, #4, or #5?
What is the full form of #1?

1. the full form? It is absolutely correct s it is. That talks about NOW, Present Tense.

2. this talks about the FUTURE
3. This is Conditional but should is not used very often; would is used more often.
4. this is also NOW, Present, implying that there is no one able to help me.
5. check spelling of "who" and this obligatory = if some one HAS to help that means they "should!"

Sra