The Blessed Buddha once explained:
Friends, the uninstructed, uneducated, and ordinary person neither understands
the origin as it really is, nor does he understand the ceasing, nor the satisfaction, 
nor the danger, nor the escape from these five clusters of clinging: Form, Feeling,
Perception, Mental Constructions, and Consciousness! 
But, friends, the instructed Noble Disciple understands the origin as it really is,
including the ceasing, the satisfaction, the danger, and the escape in the case of
form, feeling, perception, mental constructions, & consciousness!

How are these 5 aspects of the 5 clusters of clinging to be understood?
The origin of form is nutriment! Ceasing of nutriment is ceasing of form!
The satisfaction in form is the pleasure, fun, and joy derived from form.
The danger in form is the impermanent and decaying nature of all form.
The escape from form is the overcoming of all desire & lust for any form.
[Nutriment is here defined as: Food, contact, intention and consciousness!]

The origin of feeling, perception and construction is this sense contact.
The ceasing of feeling, perception and construction is ceasing of contact.
The satisfaction in feeling, perception & construction is the pleasure, and
joy derived from feeling, perception and mental construction.
The danger in feeling, perception and mental construction is the inherent
and inevitable impermanence & therefore immanent dissatisfaction with
any feeling, any perception and any mental construction whatsoever!
The escape from feeling, perception and construction is the overcoming
of all desire and lust for all feeling, perception and mental construction!

The initial origin of consciousness is mental construction. The ceasing of
consciousness is the ceasing of mental construction. The satisfaction in
consciousness is the pleasure and joy derived from consciousness.
The danger within consciousness is this impermanence, nature to change,
and thus misery characteristic of any form and event of consciousness!
The escape from all consciousness is the overcoming & elimination of all
desire and lust for any form of consciousness.  In this way are these 5
aspects of the 5 clusters of clinging to be fully understood! It is only in
this way, that the instructed Noble Disciple indeed really understands,
what should be understood...

More on the 5 Clusters of Clinging (Khanda):  House_on_Fire
The 5 Clusters of Clinging, The Leash, Fingernail of Soil, Certain_Rightness
~ acquisition of Acquisition of Fuel, What are the 5 Clusters of Clinging,
~ as changing, painful & non-self Any Kind, Like_Foam, The_Burning_Five,
~ as ownerless Not Yours, Clustered_Truths, Stilling_of_Clinging, khandha,
~ as categories Things_that_can_be_clung_to, Not_Who_but_What,
~ as suffering Clustered_Truths, Breaking_the_Bonds, Burden_and_Prison,  

Source:
The Grouped Sayings by the Buddha. Samyutta Nikāya 22:74 III 822
http://www.pariyatti.com/book.cgi?prod_id=948507
http://www.accesstoinsight.org/canon/samyutta/index.html