Elvish Script

Elvish script is written from top to bottom, then right to left. This writing system is used by Elvish, Undercommon, Deep Drow, and Sylvan.
Each phoneme or "letter" has four components: two shapes, and those shapes' orientations. There are three possible shapes and two possible orientations. The shapes are referred to as "leaf", "rose", and "thorn", while its possible orientations are referred to as "left" and "right".

ORIENTATION ↕ SHAPE ↔	Leaf	Rose	Thorn
Left
Right

A leaf is a long, thin loop. A rose is a small circle, usually smaller than a leaf. A thorn is a sudden sharp angle. In most Elvish dialects, a sentence is referred to as a vine.

TOP ↕ BOTTOM ↔	Left Leaf (LL)	Right Leaf (RL)	Left Rose (LR)	Right Rose (RR)	Left Thorn (LT)	Right Thorn (RT)
Left Leaf (LL)	LLLL ɜ/r, ur	LLRL ŋ/n	LLLR p	LLRR g	LLLT unused	LLRT aɪ/ai, ay, ey
Right Leaf (RL)	RLLL ʧ/ch & ʨ/ch or tch	RLRL ʌ/o, u, uh	RLLR m	RLRR t	RLLT oʊ/ow, o, ou	RLRT unused
Left Rose (LR)	LRLL k	LRRL u	LRLR l	LRRR n	LRLT eɪ/ae, ey, ei	LRRT s
Right Rose (RR)	RRLL ʀ/h & ɦ/h	RRRL b	RRLR o, oh	RRRR v	RRLT z	RRRT ð/th or dh
Left Thorn (LT)	LTLL aʊ/au, ow, aw	LTRL j/y	LTLR ɑ/a	LTRR θ/th	LTLT d	LTRT unused
Right Thorn (RT)	RTLL ɛ, e	RTRL unused	RTLR unused	RTRR ɹ/r	RTLT i	RTRT ʔ/'

Example Sentence

A curved "S" shape is put in between different words. If a sentence stretches too long and must be continued on the next like, that line will end with this "S" shape and the next line will begin with the same "S" shape. To the left is what a sentence written in Elvish Script looks like. If you want to translate a sentence into readable phonemes, you should start by grouping up the individual shapes into groups of two. Because each letter composes of two shapes, there should always be an even number. Using shape/orientation notation, you can mark the pairs, then reference the above table to relate it to the correct phoneme.
If you count correctly, you should see two words. This phrase should have 14 shapes in the first word, and 8 shapes in the second - meaning that the first word has 7 letters in it, and the second has 4.

Translation

Once you've grouped the segments of shapes together and found what phoneme relates to each of them, you can then check what it means in its dictionary. However, you still have to figure out what language or dialect it is in. You could do so using the context of the situation - for instance, if you see this writing while traversing the Underdark, you could most assuredly assume it is written in Deep Drow. However, the writing to the left contains a phoneme that isn't present in Deep Drow -- RRRL, or "b". If you find a letter not present in one language, that is a pretty good indicator of what language you're dealing with. From then it's just figuring out the dialect. Deep Drow is easy - it has no written dialects, as High Drow is only a verbal language. However, Elvish itself has quite a few.
For this exercise, assume you found this script in an inn, written aside multiple other scripts. You could assume then that it's written in Standard Elvish, because if it's in the context of other languages it is meant as a translation that can be read by anyone with Elvish knowledge, and translations are always written in Standard. Knowing this, you could search for "trugnob krath" in the Standard Elvish dictionary.

... And if you've ever programmed anything, you'll know exactly what this phrase means -- Hello World!

Phonology

* keep in mind, this is just an approximation of what these phonemes may actually sound like. to get a full idea of what the sound is, click the links included.

Consonants

Phoneme	Example
m (voiced bilabial nasal)	Human, Matter
n (voiced alveolar nasal)	Human, Banana
ŋ/n (voiced velar nasal)	Walking, Winged
p (voiceless bilabial plosive)	Pink, Apple
b (voiced bilabial plosive)	Bird, Abnormal
t (voiceless alveolar plosive)	Tan, Attack
d (voiced alveolar plosive)	Danger, Deer
k (voiceless velar plosive)	Carrot, Black
g (voiced velar plosive)	Great, Aggravate
ʧ/ch (voiceless postalveolar affricate)	Cheese, Attach
ʨ/ch or tch (voiceless alveolo-palatal affricate)	Cheese, Attach
s (voiceless alveolar fricative)	Sweet, Assign
z (voiced alveolar fricative)	Zoo, Bazaar
j/y (voiced palatal approximant)	Yellow, Yule
ɹ/r (voiced alveolar approximant)	Realize, Ferret
ɹ/r (voiced alveolar approximant)	Realize, Ferret
ʀ/h (voiced uvular trill)	German "ch"
ɦ/h (voiced glottal fricative)	Hello, Hero
v (voiced labiodental fricative)	Vest, Lever
θ/th (voiceless dental fricative)	Thick, Nothing
ð/th or dh (voiced dental fricative)	This, Leather
l (voiced alveolar lateral approximant)	Love, Well
ʔ/' (glottal stop)	(in British English) Butter, Button

Vowels

Phoneme	Example
ɑ/a (open back unrounded)	Father, Palm
i (close front unrounded)	Wheat, Free
u (close back rounded)	Lose, Soon
ɛ, e (mid front unrounded)	Bet, Collect
o, oh (open-mid back rounded)	Not, Wasp
ɜ/r, ur (open-mid central unrounded)	Curl, Burly
ʌ/o, u, uh (open-mid back unrounded)	But, Love
aɪ/ai, ay, ey (dipthong)	Bye, While
aʊ/au, ow, aw (dipthong)	Loud, Bounce
eɪ/ae, ey, ei (dipthong)	Lay, Wait
oʊ/ow, o, ou (dipthong)	Dome, Own