the great pyramids of egypt were built thousands of years ago. they were made up mainly of blocks of…

the great pyramids of egypt were built thousands of years ago. they were made up mainly of blocks of limestone, a kind of rock used for building. over the centuries, the pyramids began to fall apart. in the early 1980s, workers began repairing them. they were puzzled when the limestone blocks began breaking. finally they found the answer. using modern cement for the repairs turned out to be a mistake. water in the cement had damaged the limestone. the workers decided to fix the pyramids in the same way they had been built. they used blocks fitted neatly together. after that, the work was a success. what is the main, or central, idea of the passage? using modern cement to repair the great pyramids was not a successful approach. workers discovered that ancient ways of repairing the great pyramids worked better than modern ways. workers began repairing the great pyramids in the early 1980s.

the great pyramids of egypt were built thousands of years ago. they were made up mainly of blocks of limestone, a kind of rock used for building. over the centuries, the pyramids began to fall apart. in the early 1980s, workers began repairing them. they were puzzled when the limestone blocks began breaking. finally they found the answer. using modern cement for the repairs turned out to be a mistake. water in the cement had damaged the limestone. the workers decided to fix the pyramids in the same way they had been built. they used blocks fitted neatly together. after that, the work was a success. what is the main, or central, idea of the passage? using modern cement to repair the great pyramids was not a successful approach. workers discovered that ancient ways of repairing the great pyramids worked better than modern ways. workers began repairing the great pyramids in the early 1980s.

Answer

Brief Explanations:

The passage first mentions workers using modern cement (which failed as it damaged limestone). Then it states they decided to fix the pyramids the same way they were built (ancient method) and the work was a success. This shows a comparison between ancient and modern repair methods.

Answer:

Workers discovered that ancient ways of repairing the Great Pyramids worked better than modern ways.