Define the following term：blending

Define the following term：blending

BLENDING IS THE FORMATION OF NEW WORDS BY COMBINING PARTS OF TWO WORDS OR A WORD PLUS A PART OF ANOTHER WORD. BLENDING IS A VERY PRODUCTIVE PROCESS AND MANY COINAGES RESULTING FROM BLENDING HAVE BECOME WELL-ESTABLISHED. MOREOVER, THEY EVEN SERVE AS MODELS FOR NEW FORMATIONS. AS FAR AS THE STRUCTURE IS CONCERNED, BLENDS FALL INTO FOUR MAJOR GROUPS: (1) HEAD +TAIL ; (2) HEAD + HEAD; (3) HEAD + WORD; (4) WORD + TAIL.