Statements:
All consonants are alphabets.
All alphabets are vowels.
Conclusions:
I. All consonants are vowels.
II. Some alphabets are not consonants.
All consonants are alphabets (A) + All alphabets are vowels (A) = All consonants are vowels (A). Hence, conclusion I will follow. All consonants are alphabets (A) ⇒ conversion ⇒ Some alphabets are consonants (I). Hence, conclusion II will not follow.