"I Don't Know" is Mika Nakashima

Mika Nakashima

is a Japanese singer, model, and actress. She has achieved five number-one albums in Japan and also embarked on an acting career, most notably in the live-action movie Nana, based on the manga of the same name.- Early life and debut :...

's 26th single

Single (music)

In music, a single or record single is a type of release, typically a recording of fewer tracks than an LP or a CD. This can be released for sale to the public in a variety of different formats. In most cases, the single is a song that is released separately from an album, but it can still appear...

, released on July 23, 2008. It is a collaboration with owarai

Owarai

is a broad word used to describe Japanese comedy as seen on television. The word owarai is the honorific form of the word warai, meaning "a laugh" or "a smile". Owarai is most common on Japanese variety shows and the comedians are referred to as owarai geinin or owarai tarento...

group Morisanchuu (森三中), released under the name Mica 3 Chu (Mikasanchuu), and is her first single to be released as a CD+DVD format in addition to the regular CD only format.

'I Don't Know' is Mika's first English-language single. 'I Don't Know' and its B-side, 'Shut Up,' are sung entirely in English.

Oricon sales chart (Japan)

Release	Chart	Peak Position	Sales Total	Chart Run
July 23, 2008	Oricon Daily Singles Chart	6	17,708	5 weeks
	Oricon Weekly Singles Chart	11
	Oricon Monthly Singles Chart	—
	Oricon Yearly Singles Chart	392

External links

• http://www.mikanakashima.com/
• http://www.kumonoito.net/