1)is there any case that we can use "would" after "if" in conditionals?
2)Is there a possibility that "should" will be on the begining of a sentens and it won't be a QUESTION?
3)What is the inversion in the second conditional?
1. Yes, you can use "would" after "if" in conditionals when:
a) "would" = "want to" e.g.
"If you would know the value of money, try to borrow some from a friend" = "if you want to know the value of money..." [This usage may sound old-fashioned.]
b) "would" = "(be) willing to", e.g.
"If you would only listen, you would find out something to your advantage!" = "if you were only willing to listen..."
c) "would" expressing "politeness" or "deference", e.g.
"If you would just sign here, sir, I'll get your room keys."
2. Yes, "should" can start a non-questioning sentence in certain conditional statements:
a) Should you require any further assistance, please let me know = if you require further assistance, please let me know.
b) Should Napoleon's army arrive before 6 o'clock, Wellington will be in trouble = if N's army arrives before 6, W. will be in trouble.
3. Inversion in the 2nd conditional is moderately common, e.g.
a) Were you to require further treatment, all your expenses would be paid by your medical insurance provider = if you were to require further treatment...
b) I'm wondering what would happen, were I to ask the same question = if I were to ask the same question, what would happen, I'm wondering.