Statements: All consonants are letters.
All letters are noun.
No noun is pronoun.
Conclusions:I. All nouns are letters.
II. All consonants are noun.
All letters are noun(A) ⇒ conversion ⇒ Some noun are letters(I). Hence conclusion I does not follow. All consonants are letters(A) + All letters are noun(A) ⇒ All consonants are noun(A). Hence conclusion II follows. Alternate method: