1. CIRYA "ship" (an R-plural)
Singular: nominative cirya "a ship", (accusative ciryá in archaic Book Quenya only,) dative ciryan "for a ship", genitive ciryo "a ship's, of/from a ship", possessive ciryava "of a ship", locative ciryassë "on/in a ship", allative ciryanna "to a ship", ablative ciryallo "from a ship", instrumental ciryanen "with/by a ship", respective ciryas (meaning unknown).

Plural: nominative ciryar "ships", (accusative ciryai in Book Quenya, later ciryar,) dative ciryain, genitive ciryaron, possessive *ciryaiva (not in Plotz), locative ciryassen, allative ciryannar, ablative ciryallon (or *ciryallor, not in Plotz), instrumental ciryainen, respective ciryais.

Partitive plural: nominative ciryali *"some ships" (in archaic "Book Quenya" ciryalí both in the nominative and the accusative), dative ciryalin, genitive ciryalion, possessive ciryalíva, locative ciryalissë or ciryalissen, allative ciryalinna or ciryalinnar, ablative ciryalillo or ciryalillon, instrumental ciryalínen, respective ciryalis.

Dual: Nominative ciryat "two ships, a couple of ships" (no distinct accusative even in archaic Quenya?), dative ciryant, genitive ciryato, possessive ciryatwa, locative ciryatsë, allative ciryanta, ablative ciryalto, instrumental ciryanten, respective ciryates. In the case of a u-dual, however, duality is already sufficiently expressed by the suffix -u, so the normal case endings with no t are (presumably) used: Nominative aldu "two trees", (accusative *aldú,) genitive *alduo, possessive *alduva, dative *alduen, allative *aldunna, ablative *aldullo, locative *aldussë, instrumental *aldunen, respective *aldus.

2. LASSË "leaf" (an I-plural)
Singular: Nominative. lassë "leaf", (acc. lassé,) dative lassen "for a leaf", genitive lassëo "a leaf's", possessive lasséva "of a leaf", locative lassessë "in/on a leaf", allative lassenna "to a leaf", ablative lassello "from a leaf", instrumental lassenen "with a leaf", respective lasses (meaning unknown).

Plural: Nom. lassi "leaves", (acc. lassí,) dat. lassin, gen. lassion, poss. *lassiva (not in Plotz), loc. lassessen, all. lassennar, abl. lassellon or lassellor, inst. lassenen, resp. lassis.

Partitive plural: Nom. lasseli (in "Book Quenya" lasselí both in nom. and acc.), gen. lasselion, poss. lasselíva, dat. lasselin, loc. lasselisse/lasselissen, all. lasselinna/lasselinnar, abl. lasselillo/lasselillon, instr. lasselínen, resp. lasselis.

Dual: Nom/acc lasset "a couple of leaves", dat. lassent, gen. lasseto, poss. lassetwa, loc. lassetsë, all. lassenta, abl. lasselto, inst. lassenten, resp. lassetes.

The Plotz letter gives no example involving a noun ending in a consonant, but it must go something like this:

3. NAT "thing"
Singular: Nominative nat "thing", dative *naten "for a thing", genitive *nato "a thing's", possessive *natwa "of a thing", locative *natessë "in/on a thing", allative *natenna "to a thing", ablative *natello "from a thing", instrumental *natenen "by/with a thing", respective *nates (meaning unknown).

Plural: Nom. *nati "things", (acc. *natí,) dat. *natin, gen. *nation, poss. *nativa, loc. *natissen, all. *natinnar, abl. *natillon or *natillor, inst. *natinen, resp. *natis.

Partitive plural: Nom. *nateli (in "Book Quenya" *natelí both in nom. and acc.), dat. *natelin, gen. *natelion, poss. *natelíva, loc. *natelisse/natelissen, all. *natelinna/natelinnar, abl. *natelillo/natelillon, instr. *natelínen, resp. *natelis.

Dual: Nom/acc *natu "a couple of things" (the ending -u being preferred since the stem ends in a t): dat. *natuen, gen. *natuo, poss. *natuva, loc. *natussë, all. *natunna, abl. *natullo, instr. *natunen, resp. natus. But a consonant stem not ending in -t or -d, like elen "star", would presumably go like this: Nom/acc. *elenet "a couple of stars", dat. *elenent, gen. *eleneto (*elento?), poss. *elenetwa, loc. *elenetsë, all. *elenenta (perhaps contracted to *elenta), abl. *elenelto, inst. *elenenten (perhaps contracted to *elenten), resp. *elenetes (*elentes?).

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