The many prefixes, infixes and suffixes that you may come across when learning Celinese can be quite confusing at first, but since the language makes a lot of use of these affixes to create meaning. once one gets used to how they can create words, the Celinese learner's vocabulary is greatly expanded. Suffixes are built (unless an exception is noted) by taking a verb or noun, removing its ending (i.e. moirí would be reduced to moir, laiðí to laið or chenos to chen), then adding the appropriate suffix.
-ír: -ír is used to denote someone or something that carries out the specific verb. Thus, moirí (fight) becomes moirír (fighter, soldier). Laiðí (to sing) becomes laiðír (one who sings.) This ending can be attached to any verb in Celinese; so 'teısí' (to prosper or to fare well) becomes 'teısír' (one who prospers.)
-oê: 'oê' is perhaps the common suffix in Celinese alongside -os. The former is used as an abstract nominaliser, the latter as a concrete one. Two illustrative examples are cailí (to travel) and cyrí (to agree). Cailos is used to refer to a specific trip - e.g. "mo g-cailos lo r-Iferðí" (my trip to Iferðí) and cyros to a specific agreement - such as "cyros parom tystírain elithoëg hynðo w-frochynansêim" (the agreement between the Elithoan states on the reduction of pollution.) Cailoê and cyroê, on the other hand, refer to something less concrete - the process of travelling and the state of deliberating.
-air: in many ways, 'air' is a counterpart to 'oê'. Whilst the latter describes the time or state after an action took place, the former describes a time or state during which an action is taken - norair is night (time of continued darkness), mereð-séilair is happiness (time of continued "good sun" - i.e. positive feeling) and winter is féifrair (time of continued frost).
-ast: This ending is somewhat similar to '-ful', but unlike in English, it is usually attached for verbs, rather than nous. It suggests a full possession of the quality expressed in the verb. Thus, if to pay attention is gachtí, someone or something that is attentive or careful (i.e. characterised by fully paying attention) could be described as gachtast. To care is êdithí - someone who is caring or considerate (characterised by fully caring) is êdithast. The opposite is wynt - gachtwynt and êdithwynt being possible ways of saying unattentive and uncaring.
-eg/ig: The standard way to create adjectives, it can be attached to nouns or adjectives. E.g. caiðí is to show, caiðeg is evident, but also, through semantic shift, happy; brochí is to need - brochig is needy.
-am: Am is used to make intensive adjectives, which often carry a sense of an action or state being 'excessive.' These can be formed by chopping off the -eg/-ig ending and replacing it with am, or sticking am onto the ending of an adjective if it ends in another manner. Thus thyreg is the Celinese adjective for sweet; thyram is sickly sweet, saccharine. Foireg is cold, foiram is bloody freezing or bitter. Am appears as an infix to make 'excessive verbs' too, and to make something even more excessive, one adds -an as well as -am: twymaman suggests (exaggeratedly) that it is physically impossible to get any hotter than it is now.
Whilst -am is often used negatively, it also has a positive connotation: whilst the English "big man" is often used disparagingly and sarcastically in English, its counterpart ðywysam is very positive, suggesting a generous, amiable person. Mildam ("big friend") is used to refer to close friends.
-och/-ín: Och and ín are used for the opposite of -am, as a diminutive that indicates that something is small - e.g. thúl (house) > thúloch (small cottage) or thúlín (outhouse); dosnë (dog) vs dosnoch (lap dog) or dosnín (puppy); twym (hot) vs twymoch (tepid). -och can often be used negatively - see the difference between poreg athlë or athlín (small town) and athloch (little burg) - with -ín generally being considered to apply to things that are positive and endearing, but not always. To indicate that something is bad, but not small, one uses a combination of diminutive and augmentative, -ocham (athlocham, shithole).