It always surprises me. Nature has many secrets. Two elements with totally different qualities, when mixing together produce yet another product with no sign of the qualities of either of the elements. Chlorine and sodium both corrosive by nature (and also poisonous and harmful) combine together and form sodium chloride which is relished by both men and animals. But how strange the same rule applies to English words also ! The word break, in isolation means one thing. (eg. a mud pot falling down and breaking into pieces) But in combination with other words, a total transformation takes place. If it is cloud-break, it is rain. If it is break-up of marriage, it is divorce. If it is house-break, it does not mean the collapse of the house. It means theft. So with the two innocent words break and through. Independently they are different in meaning. But together, they assume a different sense – make a way through an obstacle. Some scientific inventions and discoveries also are termed using this phrase. But what I do not understand is why the same rule does not apply when two political parties or two nations with dissimilar political ideologies ally together.