There is another very predictable aspect of Latin present participles that is good to learn at the outset. In the Latin language, abstract nouns were often formed from present participle bases, by the addition of the common suffix -ia. If the base patient– denoted “suffering” in an adjectival sense—as today a patient person is a (long-)suffering person—then the derived noun patient-ia denoted the act or state of suffering—English patience. Way back in Chapter 2 (§14), we saw that Latin -tia often evolves into English -ce; patience is only one of many words to have undergone that change. Thus we can associate the verbal adjective eloquent-, “speaking out” (> E eloquent) with its abstract noun eloquentia (> E eloquence). There is a slightly different phonetic change that sometimes occurs in the transmission to English: the -ntia of the abstract noun may become, not -nce, but -ncy. A good illustration is the Latin noun formed from the present participle constant– (“standing together”)—constantia (“a firm stand,” “steadiness”), which comes into English as constancy. Without the prefix, however, Latin stantia was the source of English stance, which joins status, station, and stature as yet another abstract noun that means a “standing.”
To summarize, then, we can expect to find English adjectives in -ant or -ent that have kept the original base form of Latin present participles, alongside corresponding nouns in –ance (-ancy) or –ence (-ency) that are derived from Latin abstract nouns in -ia. These patterns are very regular and dependable; once you understand the basic formation of the Latin present participle, you will start recognizing countless English words that come from that source. If you have learned Latin verbs by conjugation type, you may even know whether to spell these English words with an a (1st conjugation) or an e (all the rest).