I'm new to R and unable to find other threads with a similar issue. I'm cleaning data that requires punctuation at the end of each line. I am unable to add, say, a period without overwriting the final character of the line preceding the carriage return + line feed. Sample code: Data1 <- "%trn: dads sheep\r\n*MOT: hunn.\r\n%trn: yes.\r\n*MOT: ana mu\r\n%trn: where is it?" Data2 <- gsub("[^[:punct:]]\r\n\\*", ".\r\n\\*", Data1) The contents of Data2: [1] "%trn: dads shee.\r\n*MOT: hunn.\r\n%trn: yes.\r\n*MOT: ana mu\r\n%trn: where is it?" Notice the "p" of sheep was overwritten with the period. Any thoughts on how I could avoid this?