No disprespect intended, but skipping the spelling of elsif -v- elseif issue, if you bought books which show indentation done that way, I suggest you take them back and see if you can get your money back.:^)
Examine what is said, not who speaks.
1) When a distinguished but elderly scientist states that something is possible, he is almost certainly right. When he states that something is impossible, he is very probably wrong.
2) The only way of discovering the limits of the possible is to venture a little way past them into the impossible
3) Any sufficiently advanced technology is indistinguishable from magic.
Arthur C. Clarke.