"This year is your last year."
Translation:DISlIj Qav 'oH DISvam'e'.
You may have seen a similar sentence without the -'e', but this exact sentence without the -'e' is ungrammatical, so if you see it that way, please comment on it so we can fix it.
The -'e' suffix can be used in a few slightly different situations, but most of them are completely optional and the effect of the -'e' is usually very subtle. Often, the -'e' suffix doesn't have a good translation in the English sentence, so there is no way for you to guess, by looking at the English sentence whether we have included an -'e' in the Klingon sentence or not. In those situations we try to enter accepted translations both with and without the optional -'e'. However, this sentence is not one of those cases. For this sentence, the -'e' is required and not optional.
When using a pronoun as the verb "to be", like in this sentence, that pronoun is acting as both the subject and the verb. DISlIj Qav 'oH is a complete sentence meaning "It is your last year." The 'oH in this sentence is a pronoun acting like a verb, but also representing the subject. In standard OVS sentences, you cannot use a pronoun for the subject and also use an explicitly stated noun - you have to choose whether to use the noun, itself, or use a pronoun to refer to the noun. On the other hand, in these sorts of "to be" sentences equating two nouns or nouns phrases, you don't have the option of using the noun, itself - you MUST use the pronoun to act as the verb. So a very special grammar exists in such a case so that if you want to explicitly state the noun (i.e. tell us what "it" is) you place that noun after the pronoun and mark it with -'e'. If you do not state the subject noun and just leave the pronoun (as in DISlIj Qav 'oH), you don't need the '-e'. But if you do state the subject noun (as "this year" in the sentence given here), you are required to mark that subject noun with -'e': DISlIj Qav 'oH DISvam'e'.
I hope that was clear, but if not, please ask more questions.