This site has an introduction to the concept of direct objects and their pronouns, that focuses on their use in sentences with verb infinitives. Ample examples illustrate the formation and placement of direct object pronouns. Students may check their mastery of this principle with a quiz that follows the lesson.

This site has a good explanation of the use of "hacer," in the preterite tense with time expressions to mean "ago." Examples in Spanish and English supplement the explanation. A short test at the end of the lesson tests the student's mastery of this grammar principle.

This site is an introduction to the concept of indirect objects and their pronouns. Ample examples illustrate the formation and placement of indirect object pronouns.Students may check their mastery of this principle with a quiz that follows the lesson.

This website is a lesson on indirect objects and their pronouns. Good explanation of their use in negative sentences. Ample examples illustrate the formation and placement of indirect object pronouns. Students may check their mastery of this principle with a quiz that follows the lesson.

Online lesson on indirect objects and their pronouns. Good explanation of their use in sentences that include verb infinitives. Ample examples illustrate the formation and placement of indirect object pronouns. Students may check their mastery of this principle with a quiz that follows the lesson.

Excellent lesson on irregular comparatives and superlatives, which include mejor, peor, mayor, and menor. The lesson is thorough and easy to understand, with ample examples. A quiz at the end of the lesson tests the student's mastery of this grammar principle.

Excellent lesson on negation in Spanish. A list of affirmative words with their negative counterparts is presented. Examples of negative sentences enhance the explanation. A short test at the end of the lesson tests the student's mastery of this grammar principle.

Great lesson on the use of por and para. Ample examples illustrate the rules for their application. A quiz follows the lesson to test the student's mastery of por and para.

This site is a lesson on possessive adjectives.An adequate number of examples enhance the explanation. The student can test his mastery of the grammar principle with a short quiz at the end of the lesson.

This explanation of possessive pronouns in Spanish offers examples that illustrate their use. Students may test their mastery of this concept with a quiz that follows the lesson.

This explanation of the present progressive tense includes stem-changing present participles and those that involve spelling changes. Examples illustrate this grammar principle and a test assesses student mastery of the content.

Great lesson for identifying words and phrases that indicate which past tense to use, preterite or imperfect. Though not meant to be a comprehensive lesson on the application of these two past tenses, the two lists of time expressions provide students with a quick and practical start to using the preterite and imperfect tenses.A quiz at the end of the lesson tests the student's mastery of this grammar principle.

This site is an introduction to verbs that change meaning according to which past tense is applied, preterite or imperfect. Examples in English and Spanish illustrate the change of meaning. A quiz at the end of the lesson tests the student's mastery of this grammar principle.

Fantastic explanation of relative pronouns with an introduction to using the Spanish relative pronoun "que." Ample examples in Spanish and English illustrate the use of "que," as a relative pronoun. Students may test their understanding of the relative pronoun "que," with a quiz that follows the lesson.

An excellent introduction to using the Spanish relative pronoun "quien," that contrasts its use with the pronoun "que," Ample examples in Spanish and English illustrate this principle. Students may test their understanding of the relative pronouns "quien," and "que," with a quiz that follows the lesson.

After a brief review of what verbs and verb infinites are, this site offers a comprehensive explanation of subject pronouns. A great comparison of Spanish subject pronouns to English subject pronouns. Differences between second person pronouns tu, usted, ustedes and vosotros are explained. Great lesson for understanding subject pronouns.

Great explanation of how to conjugate the six irregular verbs in the present subjunctive: dar, estar, haber, ir, saber, and ser. A quiz at the end of the lesson tests the student's mastery of irregular conjugations in the present subjunctive.

Comprehensive lesson on how to conjugate verbs in the present subjunctive. Regular and stem-changing verbs are presented in this explanation. A quiz at the end of the lesson tests the student's mastery of verb conjugations in the present subjunctive.

Fantastic explanation of spelling changes in the Spanish language and their effect upon conjugations in the present subjunctive. Verb infinitives that end in -car, -gar, and -zar are among those that are considered. A quiz at the end of the lesson tests the student's mastery of verb conjugations in the present subjunctive that are altered by orthographical changes.

Learn firsthand from a young Antarctic researcher about a long-term study on the reproductive history of Weddell seals in this video segment adapted from WomenInAntarctica.com. [3:33]