Except that the introduction is a big, far-reaching and systematic macro theory, the rest are similar. The preface must be signed, which is adding fuel to the fire.

Meaning, content does not need to be comprehensive, praise, promotion, and expectation; Introducers and introducers are narrower and more instructive.

The meaning of entry; The preface is second to the introduction, which can be recommended and explained as much as possible, but it should not be confused with the postscript.