My score of 8 is relative to other cartoons of the 1930s. I don't think it's really fair to compare this cartoon to the stuff of the 1940s and 50s, as Looney Tunes, Disney and MGM were making amazing cartoon shorts in this era. During the 30s, cutesy singing stuff was pretty common--and doesn't hold up as well as these later cartoons. However, this Betty Boop cartoon, for a singing one, is awfully good due to nice animation (the Fleischers were known for this) and clever gags.
This cartoon, according to IMDb, was made to thank the huge support the Boop shorts was receiving from the Japanese. So, Betty finishes a show in America and flies to Japan to thank them. Once there, she and the audience have a bit sing-a-long and the film ends.
"A Language All My Own" is very interesting because compared to the day, the Japanese people are portrayed well--not as the typical stereotypical giant-toothed folks with thick glasses (I have no idea why this image was so popular at that time). This is very nice but I am also sure that the studio shelved the cartoon during WWII, as the American people DID want outrageous stereotypes of the Japanese at that time! Worth seeing because it's so catchy and cute. So, if you are curious enough to watch it, it can be downloaded for free at archive.org--a site often linked to IMDb pages.