OK i see, i never used the module yet.
there are two errors in the module
1. in the mod_recommend.xml file you will see two '-' (hyphens) one on line 2 and on line 10, those shouldnt be there.
2. in mod_recommend.php on line 18
include ("components/com_recommend/recommend.english.php"); // language path
include ("components/com_recommend/lang/english.php"); // language path