Statement: All parrots are pigeons. Some crows are pigeon. Some sparrows are crow. All sparrows are koels. Conclusions: I. Some koels are crows. II. Some parrots are crows. III. Some sparrows are pigeons. IV. No crow is a parrot.

Some sparrows are crow + Some crows are pigeons = I + I = No conclusion Hence III does not follow. Some crows are pigeons (I) → conversion → Some pigeons are crows (I) Now, all parrots are pigeons + Some pigeons are crows = A + I = No conclusion Hence II does not follow. Nor does IV follow. However conversion II from an I-E complementary pair with IV, Hence either I or IV follows. Some sparrows are crows(I) → conversion → Some crows are sparrows + All sparrows are koels → conversion → Some koels are crows (I). Hence I.