Present Tense/Simple Past Confusion
 

I am having a difficult time memorizing simple-past endings, and now have to deal with this:

Live
vivo
vives
vive
vivimos
vivís
viven

viví
viviste
vivió
vivimos
vivisteis
vivieron

How can you tell what is meant, when a present-tense conjugation is the same as a simple-past conjugation?

Unfortunately context the only way to differentiate the present and preterit in this case. Often the tense is clarified with a word like ayer Ayer buscamos el libro.

Thanks for the help poli.

I agree with Poli: context is everything. :D
And don't try too hard to memorize; if you practice a lot, read a lot and listen a lot, conjugation will come to you naturally. ;)