dans

• Prep

  1. in, inside (enclosed in a physical space, a group, a state)
  2. to (indicates direction towards certain large subdivisions, see usage notes)
  3. in, within (a longer period of time)
  4. during
  5. out of, from
  6. in; in the works of
  7. (colloquial) Used in dans les (“about, around”)

• Noun

les

• Article

  1. plural of le: the
  2. plural of la: the

• Pron

bibliothèques

plural of bibliothèque

on

1. one, people, you, someone (an unspecified individual)
2. (informal) we

des

• Article

  1. plural of un (“some; the plural indefinite article”)
  2. plural of une (“some; the plural indefinite article”)
  3. plural of du (“some; the plural partitive article”)
  4. plural of de la (“some; the plural partitive article”)
  5. plural of de l’ (“some; the plural partitive article”)

• Contraction

au

Contraction of à le (“to the, for the, at the”).

lecteur

1. reader
2. drive, disk drive

de

• Prep

  1. of (expresses belonging)
  2. of (used to express property or association)
  3. from (used to indicate origin)
  4. of (indicates an amount)
  5. used attributively, often translated into English as a compound word
  6. from (used to indicate the start of a time or range)
  7. used after certain verbs before an infinitive, often translated into English as a gerund or an infinitive
  8. by (indicates the amount of change)

• Article
• Noun