Complex sentence: In October 1990, Metallica began recording at One on One Recording Studios in Los Angeles, California, to record the album, and also at Little Mountain Sound Studios in Vancouver, British Columbia for about a week.
Split into simpler sentences: In October 1990, Metallica entered One on One Recording Studios in Los Angeles, California, to record the album. The band also recorded the album at Little Mountain Sound Studios in Vancouver, British Columbia about a week.