Why do people often say' bragging' instead of' blowing horses'?

The expression "bragging" comes from the butcher. In the past (and now), after killing pigs and sheep, the butcher would cut a small mouth on the leg of pigs and sheep near the hoof, put an iron bar in it and poke it, then put his mouth together and blow hard into it until the pigs and sheep were swollen. This will be very convenient when peeling, and the skin will crack by itself with a slight pull with a knife. It's called blowing pigs or blowing sheep. It's bragging that you deal with cattle like this. But when slaughtering cattle, butchers rarely use this method, because cattle are huge, with tough skin and little subcutaneous fat. To blow up the whole cow, it is very human to have an extremely strong diaphragm and a huge lung capacity. Anyone who says he can brag is 99.9999 percent "bragging"! "Bragging" is also called "bragging", but people who don't know its origin will call it "bragging B" or "cow B" in order to further strengthen its derogatory meaning; Because this last word is often replaced by "X" in writing, some people now call "bragging" "awesome". When people "brag", they often look aggressive. On this basis, people describe prosperous people and things as "real cows" (greatness). The "bull" in the stock market "bull market" and "bear market" does not come from this. When the stock market rises, the trend curve will rise upwards, shaped like the outline of a bull with its head held high; When falling, the curve bends downward, similar to the drooping back of a bear's bow. In addition, another word derived from "brag" is called "brag B". In order to further strengthen the derogatory meaning of "bragging", it is abbreviated as "bragging B" or "cow B". Because this last word is often replaced by "X" in writing, some people now call "bragging" "awesome". "Niu B" means: bragging, bragging, fierce, capable, and so on. People often compare bragging to "bragging" or "bragging". Why not say "blow the horse" or something? It is said that a long time ago, there were neither bridges nor boats in the Hetao area of the Yellow River. People's common means of water transportation is a raft. Most of these rafts are made of cowhide, so people call them "cowhide rafts". "Cowhide Raft" is not public property, but people's daily means of transportation. When not in use, put it away at home; When necessary, blow enough air to the "cowhide raft" so that it can carry people floating on the water. It is not easy to brag about kayaking, but it is a very difficult task. It usually takes several people to work together to inflate the raft. Therefore, whenever someone talked big at that time, someone always replied with something like "what a big breath, you can blow a big cowhide raft". In this way, "bragging raft" is often naturally associated with "bragging". Over time, "bragging raft" has become synonymous with "bragging". "Boasting raft" is often omitted as "bragging" or "bragging". Obviously, "bragging" or "bragging" is easier to say. In this way, as a synonym for bragging, it is not a bragging raft, but a bragging or bragging. Later, in order to further strengthen its derogatory meaning, it was also abbreviated as "bragging B" or "cow B". Because this last word is often replaced by "X" in writing, some people now call "bragging" "awesome".