Complex sentence: When Sequoyah taught children to read and write with the syllabary, he reached the adults and, by the 1820s, the Cherokee had a higher rate of literacy than the whites around them in Georgia.
Split into simpler sentences: When Sequoyah taught children to read and write with the syllabary, he reached the adults. By the 1820s, the Cherokee had a higher rate of literacy than the whites around them in Georgia.