In some way 123 means "he is talented", 3456 means "talented people earn more", 45678 means "people earn more to enjoy". Then what is equal to "earn" ?

Given that 123 means "he is talented"----(a)

               3456 means "talented people earn more"------(b)

               45678 means "people earn more to enjoy".------(c)

Now we will decode what number means what word.

1---- He

2---- is

3---- the number 3 is in sentence a and b , so from these two sentences, the number 3 is common and the word Talented is common

so 3 is talented.

But 456 in sentence b and c implies the same sentence people earn more so we cant determine the particular code for earn.

so, the answer will be cant be determined.