How-to turn NOUNS into ADJECTIVES (and ADVERBS) with 的 (てき)
In the English language, words are relentlessly interchanging between word types. For example, the word “force” can be used as a noun (“a force”), a verb (“to force”), and an adjective (“forceful”).
When we talk about the specific case of turning noun words into adjectives, things can really messy in terms of what suffix we’re suppose to attach to them. Some words require the suffix “-ful” (forceful, wonderful, beautiful), some words require the suffix “-al” (mechanical, internal, musical, logical), some words require the suffix “-ous” (dangerous, fabulous, courageous). The list goes on and on.
(This isn’t even mentioning the numerous letter changes you have to do for each individual word before even adding the suffix on, e.g. “beauty” changing to “beauti” before adding on the “-ful” suffix)
Fortunately, the same process in the Japanese language is far simpler, as we only need to remember one suffix, 的 (てき). Adding the character 的 after a Japanese NOUN word will effectively turn that NOUN word into an ADJECTIVE word that means “[whatever the definition of the NOUN word is]-ish.”
効果 (“effect”) + 的 (“-ish”) = 効果的 (“effective”)
美術 (“art, fine arts”) + 的 (“-ish”) = 美術的 (“artistic”)
仮説 (“hypothesis”) + 的 (“-ish”) = 仮説的 (“hypothetical”)
When a NOUN word is turned into an ADJECTIVE word in this manner, the resulting ADJECTIVE word is always a な-Adjective and not an い-Adjective. And since all ADJECTIVE words used in this way are な-Adjectives, we can go even further and effectively use this same idea to turn NOUN words into ADVERB phrases due to the fact that all you need to turn a な-Adjective into an ADVERB phrase is the particle に appearing right after it. As such, we can have our previous three example words undergo an additional word-type transformation:
効果的 (“effective”) + に (“-ly”) = 効果的 (“effectively”)
美術的 (“artistic”) + に (“-ly”) = 美術的 (“artistically”)
仮説的 (“hypothetical”) + に (“-ly”) = 仮説的 (“hypothetically”)
Motto kouritsuteki ni nihongo ga benkyou shitai desu.
“I want to be more efficient with my Japanese studies.”
Gutaiteki na hidori wa kimatte inai.
“The exact date hasn’t been decided.”