Ways of forming compound words

Compound words in English can be formed not only by means of composition but also by means of:

a) reduplication, e.g. too-too, and also by means of reduplicatin combined with sound interchange, e.g. rope-ripe,

b) conversion from word-groups, e.g. to micky-mouse, can-do, makeup etc,

c) back formation from compound nouns or word-groups, e.g. to bloodtransfuse, to fingerprint etc,

d) analogy, e.g. lie-in (on the analogy with sit-in) and also phone-in, brawn-drain (on the analogy with brain-drain) etc.