Nouns that end in a vowel add
s to form the plural, those that end in a consonant add
-es. Long words in "-ium" add
Li serpente, li seprentes. Li structura, Li structuras. Li circul, li circules. Li person, li persones. Li vocabularium, li vocabulariums.
There is one exception to the rule given above. Words in "-c" and "-g" add only
-s in order to preserve the hard sounds.
Li plug (plough), li plugs. Li flanc (side), li flancs.
Adjectives normally come before the noun but they can be placed after if so desired.
Un nigri cate (a black cat). Un lingue universal (a universal langauge). Li table es solid.
It is sometimes necessary for euphonic reasons to add a vowel at the end of a root. We can us
-e for general purposes. This is usually regarded as more specifically applicable to nouns ; for adjectives we add
-i (compare English "easy", "stringy"). these endings are frequently optional though there is a tendency to standardisation. In some cases the endings are really necessary.
Un povri fémina (a poor woman). Li nocte es obscur (the night is dark). Harmonie es un facte.
Adjectives, of course, do not normally take the plural "-s" unless they are used without nouns.
Maria have li verdis e Rosa have li bluis (Mary has the green ones and Rose has the blue ones).
Adverbs are formed from adjectives by the addition of the suffix
-men ; the final "-i" can be retained if it helps the pronunciation.
Nationalmen (nationally), rigidmen (rigidly).
In many cases however the adjective itself can be used.
Li fémina lude bon (or bonmen), (the woman plays well)
Li tigre atacca violentmen. Li puella vade delicatmen along li strade. Li dictionariums es important. Li fémina porta un gay blu robe. Li mann have mult moné. Bell flores es un grand plesura.