Linguistics can be summarized in one line:

and the rest is literature.
In order to listen carefully to whatever tongue someone else is speaking, one must lend an ear first to his mood, comes next to his metre, then to his tone, and lastly to the vowels, followed by the consonants.

Any equivalence relation between human beings, e.g., equality, must be reflexive, symmetric, and transitive. Without even knowing perfectly what somebody else is trying to convey, any Tom, Dick, or Harry can conceive whether the speaker feels happy, angry, glad, or sad. As follow are grammatical moods, for instance, the indicative mood, the imperative mood, the infinitive mood, and the subjunctive mood, as in English.

For anything said, you can count the syllables, tap the beat, hear the rhythm, or imitate the speech. You can make sense of the bites of word, the sets of phrase, and the parts of speech; you may also parse a sentence and analyse the syntax; furthermore, you will differentiate between an agglutinative and an inflectional language.

There are high, middle, and low pitches, as in Thai; stressed and unstressed syllables, as in German; primary or secondary accents, as in Italian; penult or antepenult, as in Latin; the acute, the grave, or the circumflex, as in French; the upper, the lower, the even, and the oblique tones, as in Mandarin; the rise and fall, the sharp or flat, of tunes, for the affirmative, the negative, the interrogative, or the exclamatory tones, as in Russian; and a deep, a loud, a soft, a shrill, or a thick voice, as annotated by diacritics.

All are based on a, e, i, o, u. There are open vowels and close vowels; short or long vowels; front, central, or back vowels; written or spoken vowels; monophthong, diphthong, and triphthong; masculine, feminine, or neuter vowels, as in vowel harmony, etc.

Consonants classified by units are phoneme, allophone, and morpheme; by positions initial, medial, and final; by organs fricatives, nasals, uvular, glottal, labial, alveolar, and velar; and by the flow of air aspirated and unaspirated, i.e., soft and hard.
Only after you have learnt to get your priorities straight (I repeat: first mood, second metre, third tone, fourth vowels, and fifth consonants), then you will manage to attend my every word. That said, you shall have a gift for tongues.
In no time, you will be caught up with such grammatical terms as aspect, tense, voice, mood, case, class, gender, number, agreement, Sandhi, mutation, liaison, etymology, lexicology, orthography, alphabet, script, character, and what not, so much so that you are divided between literature and linguistics, out of which I prefer the former, anyway.
The every essence of literature is the war between emotion and intellect.
—Isaac Bashevis Singer
Qua grammarian, his sentiments of art and science in grammar lay to rest the struggle, thanks to i. nomenclature (e.g. synonym, antonym, metonym, and homonym); ii. rhetoric (e.g. diction, euphemism, idioms, phraseology, and proverbs); iii. figures of speech (e.g. alliteration, anastrophe, assonance, ellipsis, inversion, metaphor, and simile); iv. composition (e.g. discourse, narration, orchestration, plot, and style); and v. translation and interpretation (e.g. figurative, free, literal, and verbatim).