What kind of quantifier

What kind of quantifier

Array times

A problem of predicate logic in discrete mathematics
Suppose: 1. People (animals) who can read are literate; 2. Dolphins are illiterate; 3. Some dolphins are intelligent. Prove: some very intelligent people (animals) are illiterate. Please express the above facts with predicate logic, and then deduce the final conclusion. The process should be clearer,

x: Human (animal); R (x): X can read; w (x): X is literate; C (x): X is intelligent; D (x): X is dolphin
1.(∨x)(R(x)->W(x))
2.(∨x)(D(x)->~W(x))
3.(ヨx)(D(x)∧C(x))
Conclusion to be proved: (ヨ x) (C (x) ∧ ~ w (x))
prove:
⒈(ヨx)(D(x)∧C(x)) P
⒉D(y)∧C(y) ∨-
⒊(∨x)(D(x)->~W(x)) P
⒋D(y) T(2)
⒌C(y) T(2)
W(y) T(3,4)
W (y) ∧ C (y) 5,6 combination
⒏(ヨx)(C(x)∧~W(x)) ∨+
I don't know why the first proposition doesn't work when I prove it