Original sentence: The fourth season premiere aired on September 18, 2008, averaging its highest rating ever since its debut on The CW Network with 3.96 million viewers, a 33% surge over the season three premiere and a 1.7/5 in adults 18-49, up 42% from one year earlier and its second best rating since moving to thursdays in 2006.on April 2, 2009 against the ER finale, the show scored its highest rating in adults 18-34 (1.7/5) in two and a half years, and its best rating in 18-49 (1.6/4) and women 18-34 (1.5/4)since January
Edited sentence: The fourth season premiere aired on September 18, 2008, averaging its highest rating ever since its debut on The CW Network with 3.96 million viewers, a 33% surge over the season three premiere and a 1.7/5 in adults 18-49, up 42% from one year earlier