Some context: Rowan & Martin's Laugh-In (often simply referred to as Laugh-In) is an American sketch comedy television program that ran for 140 episodes from January 22, 1968, to March 12, 1973, on the NBC television network. It was hosted by comedians Dan Rowan and Dick Martin. Laugh-In originally aired as a one-time special on September 9, 1967, and was such a success that it was brought back as a series, replacing The Man from U.N.C.L.E. on Mondays at 8 pm (ET). The title of the show was a play on the "love-ins" or "be-ins" of the 1960s hippie culture, terms that were, in turn, derived from "sit-ins", common in protests associated with civil rights and antiwar demonstrations of the time.
The 1970-71 season brought new additions to the cast include tall, lanky, sad-eyed Dennis Allen, who alternately played quietly zany characters and straight man for anybody's jokes; comic actress Ann Elder, who also contributed to scripts, tap dancer Barbara Sharma, and Johnny Brown.  Arte Johnson, who created many memorable characters, insisted on star billing, apart from the rest of the cast. The producer mollified him, but had announcer Gary Owens read Johnson's credit as a separate sentence: "Starring Dan Rowan and Dick Martin! And Arte Johnson! With Ruth Buzzi ..." This maneuver gave Johnson star billing, but made it sound like he was still part of the ensemble cast. Johnson left the show after the 1970-71 season. Henry Gibson also departed after the 1970-71 season. Johnson and he were replaced by former Hogan's Heroes stars Richard Dawson and Larry Hovis, both of whom had appeared occasionally in the first season. However, the loss of Johnson's many popular characters caused ratings to drop further.  After winning the Academy Award for Best Supporting Actress in Cactus Flower, Goldie Hawn made a guest appearance in the third episode of the fourth season. She began the episode as an arrogant snob of an actress; however, a bucket of water thrown at her transformed her back to her giggling dumb blonde persona.  The show celebrated its 100th episode during the 1971-72 season, with Carne, Worley, Johnson, Gibson, Graves, and Tiny Tim all returning for the festivities. John Wayne was on hand for his first cameo appearance since 1968.
What is significant during season 4?
A: The 1970-71 season brought new additions to the cast
Some context: Usher was born in Dallas, Texas, the son of Jonetta Patton (nee O'Neal), from Tennessee, and Usher Raymond III. Usher spent the majority of his young life in Chattanooga: his father left the family when Usher was a year old. Usher grew up with his mother, then-stepfather, and half-brother, James Lackey (born 1984). Directed by his mother, Usher joined the local church youth choir in Chattanooga, when he was nine years old.
Usher developed a friendship with American record producer, Jermaine Dupri, with whom he co-wrote and produced several tracks for his second album, My Way, released on September 16, 1997. The album's lead single, "You Make Me Wanna...", reached number one in the United Kingdom, becoming Usher's first record to be top single; the record led to his popularity reaching in the country. It also became Usher's first gold- and platinum-certified single in the United States. The album's second single, "Nice & Slow", peaked in January 1998 at number one on the Billboard Hot 100, giving Usher his first US number-one single. In February of the same year, the single was certified platinum by the RIAA. My Way has been certified six-time platinum in the United States.  "You Make Me Wanna..." won the Best Male R&B/Soul Single at the 1999 Soul Train Music Awards. In the closing months of 1997, Usher embarked on a series of tour engagements including a spot on Puffy's No Way Out tour, dates with Mary J. Blige, and the opening spot on Janet Jackson's The Velvet Rope Tour. Usher's first concert album, Live, was released in 1999, which featured appearances by Lil' Kim, Jagged Edge, Trey Lorenz, Shanice, Twista and Manuel Seal; the album has been certified gold in the United States.  Usher made his acting debut on the UPN television series Moesha, which resulted in a recurring role on the series and subsequently his first film role in 1998's The Faculty. Usher's extracurricular activities outside of the recording industry gathered momentum over the following year as he was cast in the soap opera, The Bold and the Beautiful. He completed two more films, She's All That, and his first starring role in Light It Up. He also appeared in the Disney TV movie Geppetto.  Usher's third studio album, originally titled All About U, was slated to be released in early 2001. The first single, "Pop Ya Collar", was released in late 2000 and became a number two hit in the UK but underperformed in the United States. The album was subsequently pushed back and retooled after select tracks were later leaked to the radio and Internet. After having revised and renamed to 8701, the album was released August 7, 2001 (8.7.01). The first two singles "U Remind Me" and "U Got It Bad" each topped the Billboard Hot 100 for four and six weeks, respectively. 8701 has been certified four-time platinum in the United States.  Usher appeared in the 2001 film Texas Rangers. In February 2002, Usher won a Grammy for Best Male R&B Vocal Performance for "U Remind Me". The next year, he won the same award for "U Don't Have to Call", making Usher the only artist aside from Luther Vandross and Stevie Wonder to win this award consecutively. In summer 2002, Usher contributed vocals to P. Diddy's "I Need a Girl, Part I". The year closed out with a trio of TV series appearances, all in November, on The Twilight Zone, 7th Heaven, Moesha, and American Dreams, the latter in which Usher portrayed Marvin Gaye.
did it do well in the united states
A:
It also became Usher's first gold- and platinum-certified single in the United States. The