If in a certain language PROSE is coded as PPOQE, how is LIGHT coded in that…

In this letter-coding scheme, each letter of the word is mapped position by position: the letter in every odd position (1st, 3rd, 5th, ...) is left unchanged, while the letter in every even position (2nd, 4th, ...) is replaced by the letter two places earlier in the alphabet.

Verifying this rule against the given code PROSE -> PPOQE, letter by letter:

1. P (1st, odd position) stays P.

2. R (2nd, even position) moves back two places to P.

3. O (3rd, odd position) stays O.

4. S (4th, even position) moves back two places to Q.

5. E (5th, odd position) stays E.

Applying the same position rule to LIGHT:

1. L (1st, odd position) stays L.

2. I (2nd, even position) moves back two places to G.

3. G (3rd, odd position) stays G.

4. H (4th, even position) moves back two places to F.

5. T (5th, odd position) stays T.

Cross-check: every odd-position letter is unchanged and every even-position letter has moved back exactly two places in the alphabet, exactly mirroring the PROSE -> PPOQE mapping, so the same rule has been applied consistently to LIGHT.

So LIGHT is coded as LGGFT.