If GOLD is coded as HOME, COME is coded as DONE and CORD is coded as DOSE, how would you code SONS?

Let us look at the pattern for each letter in the words:
1. $\text{G}\stackrel{+1}{\to }\text{H}$, $\text{O}\stackrel{+0}{\to }\text{O}$, $\text{L}\stackrel{+1}{\to }\text{M}$, $\text{D}\stackrel{+1}{\to }\text{E}$. Thus, $\text{GOLD}\to \text{HOME}$.
2. $\text{C}\stackrel{+1}{\to }\text{D}$, $\text{O}\stackrel{+0}{\to }\text{O}$, $\text{M}\stackrel{+1}{\to }\text{N}$, $\text{E}\stackrel{+0}{\to }\text{E}$. Thus, $\text{COME}\to \text{DONE}$.
3. $\text{C}\stackrel{+1}{\to }\text{D}$, $\text{O}\stackrel{+0}{\to }\text{O}$, $\text{R}\stackrel{+1}{\to }\text{S}$, $\text{D}\stackrel{+1}{\to }\text{E}$. Thus, $\text{CORD}\to \text{DOSE}$.

Notice that the vowels ($\text{O},\text{E}$) remain unchanged ($\stackrel{+0}{\to }$), whereas consonants are shifted by $+1$.

Applying this rule to $\text{SONS}$:

* $\text{S}$ (consonant) $\stackrel{+1}{\to }\text{T}$
* $\text{O}$ (vowel) $\stackrel{+0}{\to }\text{O}$
* $\text{N}$ (consonant) $\stackrel{+1}{\to }\text{O}$
* $\text{S}$ (consonant) $\stackrel{+1}{\to }\text{T}$

Therefore, $\text{SONS}$ is coded as $\text{TPOT}$.