ANALOGIES

Now I want to learn about Analogy which is a famous part in SAT or GRE or GMAT etc.
I need to guess the relationship between the given stem words. Let's get started:

ORGAN : KIDNEY
- The kidney is a type of organ.

CENTRIFUGE : SEPARATE
- A centrifuge is used to separate.

LASSITUDE : ENERGY
- Lassitude means lack of energy.

FERVOR : ZEALOT
- A zealot is characterized by fervor.

AGONY : PAIN
- Agony is a greater degree of pain.

MISER : THRIFT
- A miser uses excessive thrift.

COMPLIANT : SERVILE
- Servile means excessively compliant.

LUBRICANT : ABRASION
- Lubricant prevents abrasion.

WILD : RESTRAINT
- Wild means without restraint.

LAUDABLE : PRAISE
- Laudable means worthy of praise.

BED : RIVER
- Bed is the bottom of a river.

OPTIMISTIC : SUCCESS
- No relation

DISORDER : PANDEMONIUM
- Pandemonium is a great amount of disorder.

SCRUTINIZE : TEXT
- No relatioin

POSTHUMOUS : DEATH
- Posthumous means occurring after one's death.

MALINGER : WORK
- Malinger means to avoid work.

PRECIOUS : STONE
- No relation

FAMOUS : WEALTH
- No relation

SOPORIFIC : SLEEP
- Soporific means causing sleep.