。
She put sheets on her bed.
Literal
She [topic-は] her own bed [on-に] sheets [object-を] spread.
引く ('to pull, draw, attract') is a many-meaning verb. Used here in the marginal sense of 'to lay down, spread (a sheet, mat, futon)' — but for that meaning, the standard modern kanji is 敷く (しく), and 引く in this 'spread' sense reads as slightly old-fashioned or non-standard. 自分のベッドに ('on her bed') marks the location of placement with に. シーツ ('sheet') is a loanword from English.