Portuguese Language Grammar

1. Articles
   1. Definite Articles
      1. Forms
         1. Masculine singular: o
         2. Feminine singular: a
         3. Masculine plural: os
         4. Feminine plural: as
      2. Pronunciation
      3. Agreement with Noun Gender and Number
      4. Usage of Definite Articles
         1. General vs. Specific Reference
         2. With Abstract Nouns
         3. With Proper Nouns
      5. Omission of Definite Articles
         1. In Certain Expressions
         2. After Prepositions
   2. Indefinite Articles
      1. Forms
         1. Masculine singular: um
         2. Feminine singular: uma
         3. Masculine plural: uns
         4. Feminine plural: umas
      2. Pronunciation
      3. Agreement with Noun Gender and Number
      4. Usage of Indefinite Articles
         1. Indefinite Reference
         2. Numerical Usage
      5. Omission of Indefinite Articles
         1. In Certain Contexts
         2. After Prepositions
   3. Contractions of Articles with Prepositions
      1. Contractions with "de"
         1. do (de + o)
         2. da (de + a)
         3. dos (de + os)
         4. das (de + as)
      2. Contractions with "em"
         1. no (em + o)
         2. na (em + a)
         3. nos (em + os)
         4. nas (em + as)
      3. Contractions with "a"
         1. à (a + a)
         2. às (a + as)
      4. Contractions with "por"
         1. pelo (por + o)
         2. pela (por + a)
         3. pelos (por + os)
         4. pelas (por + as)
      5. Rules for Forming Contractions
      6. Usage in Sentences