Complex sentence: The blocks in the blockchain are limited to one megabyte in size, which has created problems for bitcoin transaction processing, such as increasing transaction fees and delayed processing of transactions that cannot be fit into a block.
Split into simpler sentences: The blocks in the blockchain are limited to one megabyte in size. The one megabyte limit has created problems for bitcoin transaction processing, such as increasing transaction fees and delayed processing of transactions that cannot be fit into a block.