All nouns can be both singular or plural: nuH ("weapon") refers to a single weapon or many weapons. The absence of a plural suffix does not mean the noun is singular, while a noun without a plural suffix may still refer to more than one entity. Singular and plural are often indicated by the prefix on the verb in the sentence (see section 4.1), a full pronoun (section 5.1), or simply by context.
For example, yaS ("officer") can refer to a single officer or a group of officers, depending on other words in the sentence:
yaS vImojpu' - I became an officer.
yaS DImojpu' - We became officers.
yaS jIH - I am an officer.
yaS maH - We are officers.
In the first pair, the verb prefixes (vI- for "I", DI- for "we") signal number. In the second pair, the subject pronouns (jIH for "I", maH for "we") provide that information.
Sometimes, only context clarifies whether a noun is singular or plural. For instance, yaS mojpu' could mean "he/she became an officer" or "they became officers", depending on what the speaker and listener already know.
Fortunately, it is never incorrect to explicitly mark a noun as plural using a plural suffix. Both yaS maH and yaSpu' maH ("we are officers") are grammatically correct. However, you cannot add a plural suffix to a noun referring to only one thing. The sentence yaSpu' jIH ("I am officers") is incorrect in Klingon.
Klingon uses three plural suffixes, depending on the type of noun:
-pu' (plural for beings capable of using language)
This suffix is used for people and other intelligent beings.
yaS - officer → yaSpu' - officers
Duy - emissary → Duypu' - emissaries
-Du' (plural for body parts)
This suffix is used exclusively for body parts, regardless of the type of creature.
qam - foot → qamDu' - feet
tlhon - nostril → tlhonDu' - nostrils
-mey (general plural)
This suffix is used for non-speaking beings, inanimate objects, and abstract nouns. It may also be used with speaking beings to add a sense of "scattered all about."
mID - colony → mIDmey - colonies
yuQ - planet → yuQmey - planets
puq - child → puqmey - children (scattered everywhere)
The suffix -mey cannot be used with body parts. However, poets may violate this rule for stylistic effect - for example, tlhonmey (nostrils scattered about). Until you understand such poetic nuances, stick to the grammatical rule.
Inherently Plural Nouns
Some nouns are always plural and never take plural suffixes:
ray' - targets
cha - torpedoes
chuyDaH - thrusters
These have distinct singular counterparts:
DoS - target
peng - torpedo
vIj - thruster
The singular forms can take -mey, but this implies a scattered or disorganized arrangement:
DoSmey - targets scattered all about
pengmey - torpedoes all over the place
Even though inherently plural nouns like cha are conceptually plural, they are treated grammatically as singular nouns. For example:
cha yIghuS - Stand by torpedoes! (Note: yI- is the singular imperative prefix)
