Introduction to Tenses

Sentence Construction

Until now we have learned sentence construction in present simple and imperative form. Sentence construction in all the other tenses does not require further grammatical knowledge in terms of sentence structure, which is left exactly as it was in the Present Simple form, rather it has to do with verb conjugation in the tense we desire.
 

Use of Ser and Estar

Incorporating Auxiliary-Verbs in the Simple Tenses

Auxiliary verbs are not a part of the grammatical structure of the simple tenses (Present Simple, Past Simple, etc.). This is why we make use of the matching auxiliary verb according to the context (Ser for inherent properties, Estar for temporary states or positioning), as explained {link:1188}.


Use of Ser and Estar in Other Tenses

In tenses resembling those of English, where the auxiliary verb ‘to be’ is used as part of the grammatical structure in the conjugation of that tense, we make use of the auxiliary verb estar (rather than ser). This is due to the fact that although the sentence contains the auxiliary verb ‘to be’ (estar in Spanish), it is not the main verb in the sentence.

 
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