Answers for "why we use elif instead of if in python"

elif python

The elif statement allows you to check multiple expressions for TRUE 
and execute a block of code as soon as one of the conditions evaluates
to TRUE. Similar to the else, the elif statement is optional. However,
unlike else, for which there can be at most one statement, there can 
be an arbitrary number of elif statements following an if.

if expression1:
   statement(s)
elif expression2:
   statement(s)
elif expression3:
   statement(s)
else:
   statement(s)

python elif

if num > 0:
    print("Positive number")
elif num == 0:
    print("Zero")
else:
    print("Negative number")