Is there a way to handle multi-lines instead of processing them line by line when pasting mult-lines?

For example, when I type or paste`select host() \n`, I hope to handle it directly when encounter`\n`, but when I directly paste the text `select\nhost()\n`, I hope to not handle it directly when encounter the first `\n` and wait for the input of `host()` before processing. In summary, it is to determine whether there is any unread content after `\n`. If not, it will be processed directly. Otherwise, continue reading something like the following