moving of prepositions

[Vladv1]

1.The reason for which she left is unclear- The reason she left for was unclear.
2. She is the woman on whom I depend-She is the woman I depend on.
Why can't I move the preopsition at the end in the 1, but can in the second. Could you please help establish a pattern where I can't move the preposition. Thanks. The examples are mine.

 

[jutfrank]

Let's deal with the first sentence first.

Why she left is unclear.
The reason she left is unclear.

It's possible you also mean this:

Her reason for leaving is unclear.

If you're thinking specifically about 'for which' then you need a better example. Generally speaking, putting the preposition before a relative pronoun sounds more formal than putting it at the end of a clause but you can normally do both, grammatically speaking. Sometimes, however, there are complicating grammatical factors at play. Here's a sentence I made up:

He later made a brief but memorable appearance in 2007's Echoes of Tomorrow, for which he was nominated for an Oscar.

Try moving the preposition in that sentence. Can you do it? If not, why not? If you can, where would you put it?

 

[Vladv1]

Let's deal with the first sentence first.

Why she left is unclear.
The reason she left is unclear.

It's possible you also mean this:

Her reason for leaving is unclear.

If you're thinking specifically about 'for which' then you need a better example. Generally speaking, putting the preposition before a relative pronoun sounds more formal than putting it at the end of a clause but you can normally do both, grammatically speaking. Sometimes, however, there are complicating grammatical factors at play. Here's a sentence I made up:

He later made a brief but memorable appearance in 2007's Echoes of Tomorrow, for which he was nominated for an Oscar.

Try moving the preposition in that sentence. Can you do it? If not, why not? If you can, where would you put itwo

I can't move bacause there are two 'fors"? Thanks for the great example.