[README] Clean up grammar in --download-archive paragraph

[youtube-dl] / README.md

diff --git a/README.md b/README.md
index e01b71cff5290fbf4f50fadaa99a01d71813aa4a..20241307f11e262da30620599907577c99e67db1 100644 (file)
--- a/README.md
+++ b/README.md
@@ -834,6 +834,18 @@ You will first need to tell youtube-dl to stream media to stdout with `-o -`, an
 
     youtube-dl -o - "http://www.youtube.com/watch?v=BaW_jenozKcj" | vlc -
 
+### How do I download only new videos from a playlist?
+
+Use download-archive feature. With this feature you should initially download the complete playlist with `--download-archive /path/to/download/archive/file.txt` that will record identifiers of all the videos in a special file. Each subsequent run with the same `--download-archive` will download only new videos that and skip all videos that have been downloaded before. Note that only successful downloads are recorded in the file.
+
+For example, at first,
+
+    youtube-dl --download-archive archive.txt "https://www.youtube.com/playlist?list=PLwiyx1dc3P2JR9N8gQaQN_BCvlSlap7re"
+
+will download the complete `PLwiyx1dc3P2JR9N8gQaQN_BCvlSlap7re` playlist and create a file `archive.txt`. Each subsequent run will only download new videos if any:
+
+    youtube-dl --download-archive archive.txt "https://www.youtube.com/playlist?list=PLwiyx1dc3P2JR9N8gQaQN_BCvlSlap7re"
+
 ### Can you add support for this anime video site, or site which shows current movies for free?
 
 As a matter of policy (as well as legality), youtube-dl does not include support for services that specialize in infringing copyright. As a rule of thumb, if you cannot easily find a video that the service is quite obviously allowed to distribute (i.e. that has been uploaded by the creator, the creator's distributor, or is published under a free license), the service is probably unfit for inclusion to youtube-dl.