三言类比为五音节；
四言类比为六音节；
五言类比为八音节；
六言类比为九音节；
七言类比为十音节。
八言类比为十二音节。
九言类比为十四音节。
比如李白的《上云乐》里面纷杂多变，兼有三言、四言、五言、七言、八言、九言。我分别做了相应的类比：
金天之西，白日所没。
Beyond the sky, the west
Is where the sun does rest.
康老胡雏，生彼月窟。
A Hun, Wen K’ang as hight,
Born at the moon’s last light.
巉岩容仪，戍削风骨。
His face like a high crag,
He’s vigorous with shag.
碧玉炅炅双目瞳，黄金拳拳两鬓红。
His blue eyes sparkle and brilliantly glare;
His red sideburns go well with his blond hair.
华盖垂下睫，嵩岳临上唇。
His eyelashes his eyes equip;
His nose overlooks his upper lip.
不睹诡谲貌，岂知造化神。
Without seeing such a weird face,
How do you know God’s working grace?
大道是文康之严父，元气乃文康之老亲。
The Word is K’ang’s father looking strict and divine;
The One is K’ang’s mother whose smile lights up to shine.
抚顶弄盘古，推车转天轮。
Stroking the head of old Plate Reel;
Turning the sky, turning the wheel.
云见日月初生时，铸冶火精与水银。
Clouds spreading, the sun and moon were begot;
Fire essences and mercury were wrought.
阳乌未出谷，顾兔半藏身。
When the sun was still in the dale,
The moon was half wrapped with a veil.
女娲戏黄土，团作愚下人。
When Nuwa kneaded yellow clay,
Foolish humans were made to play.
散在六合间，濛濛若沙尘。
Dispersed all over the vast land,
These humans were like grains of sand.
生死了不尽，谁明此胡是仙真。
From birth to death, the life goes on,
Who knows this Hun is an immortal one?
西海栽若木，东溟植扶桑。
By West Sea grows a knowledge tree;
On East Shore soughs a mulberry.
别来几多时，枝叶万里长。
How many years now have gone past;
Twigs and leaves their shadows down cast.
中国有七圣，半路颓洪荒。
Middle Kingdom has seven saints;
A flood causes many restraints.
陛下应运起，龙飞入咸阳。
Your Majesty comes on to rise,
Like a dragon to Hsianyang flies.
赤眉立盆子，白水兴汉光。
Red Brows help Basin to throne;
White Water maintains Han alone.
叱咤四海动，洪涛为簸扬。
With shouts and scolds, the sea does quake;
With tides and waves, the earth does shake.
举足蹋紫微，天关自开张。
Do climb up the Emperor Star;
The Heaven Gate’s for you ajar.
老胡感至德，东来进仙倡。
The Hun is moved by your great worth;
To give you a spray, he comes forth.
五色师子，九苞凤凰。
The five-colored lion sways;
The nine-bloomed phoenix plays.
They are cocks and dogs of the Huns;
In Emperor’s town they’re good ones.
淋漓飒沓，进退成行。
They keep order,confined;
They go or come, aligned.
能胡歌，献汉酒。
Hun songs they can sing;
Han wine they here bring.
跪双膝，并两肘。
Aground they kneel there;
Their elbows they pair.
散花指天举素手。
As a fairy throws blooms with her hand fair.
拜龙颜，献圣寿。
To Him they kowtow; for His bliss they bow.
北斗戾，南山摧。
The Dippers may break; the mountains may quake
天子九九八十一万岁，长倾万岁杯。
The Son of Heaven will live long, eighty thousand years old;
A long life cup he will oft hold.
译韵诗，必须押韵且有节奏，这一点不能妥协，但如何押韵，采用何种韵式因人而异。由于韵或韵式都是类比的，除了特殊的诗体，如长相思，韵式可以相对灵活。我多用偶韵和交叉韵或隔行韵，如李白这首便是偶韵。英诗绝大部分都是抑扬格，也会根据表意的需要夹杂扬抑格。英语的格律不像汉语诗严格，总的原则是音韵和谐。诗最怕因韵害义，这一点多为批评者所诟病，所以好的译诗必须是不蔓不枝，自然天成的。
来源：赵彦春