A cylinder linkage method for a multi-cylinder internal-
combustion engine comprising connecting
piston rods (27) and pistons (28) of four or more linkage
combustion and compression reversible cylinder blocks (14A, 14B, 14C, 14D, 30A, 30B, 30C, 30D) and of reversible precompression cylinder blocks (3, 8) simultaneously by one linkage rod (26), such that the linkage rod (26) is able to drive the linkage pistons (28) to move in the same direction simultaneously and to arrive at a
top dead center or a bottom dead center or any same
stroke position between the two dead centers of all the linkage cylinder blocks simultaneously. The cylinder linkage method for a multi-cylinder internal-
combustion engine can be used to manufacture a multi-cylinder linkage compound internal-combustion engine, and further used to manufacture internal-combustion engines such as
gasoline internal-combustion engine, diesel internal-combustion engine,
natural gas internal-combustion engine etc. in combination with multi-level precompression, multi-level intercooling and
power turbine (21).