address @vsemozhetbyt's comments

Author: thefourtheye

doc/api/fs.md

@@ -2553,7 +2553,7 @@ fs.readFile('<directory>', (err, data) => {
 automatically.
 3. The reading will begin at the current position. If the file size is
 10 bytes and if six bytes are already read with this file descriptor, then
-`readFile` will return only the rest of the four bytes.
+`readFile()` will return only the rest of the four bytes.
 
 The `fs.readFile()` function buffers the entire file. To minimize memory costs,
 when possible prefer streaming via `fs.createReadStream()`.
@@ -3547,12 +3547,12 @@ fs.writeFile('message.txt', 'Hello Node.js', 'utf8', callback);
 1. Any specified file descriptor has to support writing.
 2. If a file descriptor is specified as the `file`, it will not be closed
 automatically.
-3. The writing will begin at the beginning of the file. If the file size
-is 10 bytes and if six bytes are written with this file descriptor, then
-`writeFile` will return six bytes newly written and four bytes from the file.
-For example, if the file already had `'Hello World'` and the newly written
-content is `'Aloha'`, then the contents of the file would be `'Aloha World'`,
-rather than just `'Aloha'`.
+3. The writing will begin at the beginning of the file. If the file size is 10
+bytes and if six bytes are written with this file descriptor, then the file
+contents would be six newly written bytes and four bytes which were already
+there in the file from position seven to ten. For example, if the file already
+had `'Hello World'` and the newly written content is `'Aloha'`, then the
+contents of the file would be `'Aloha World'`, rather than just `'Aloha'`.
 
 It is unsafe to use `fs.writeFile()` multiple times on the same file without
 waiting for the callback. For this scenario, [`fs.createWriteStream()`][] is