Use derivations to show:

a = b, c = fd, Ra(fc) ⊨ (a = c → fb = fc) ∧ (b = c → R(fd)(fa))

Analyze the following in reduced and expanded form, the two ways you used in the homework assignments on §6.1 and §6.2:

If Ralph is the author of the story, then he knows its ending

That is, (a) analyze at in as much detail as possible, replacing pronouns by their antecedents and aiming for a result in ordinary reduced form. And (b) analyze at again (or restate the symbolic result) in an expanded form in which unanalyzed individual terms appear only as often as in the English.