Spanish language Q&A Forum

I've read so many times about the difference between these tenses but It's like banging my head against a wall. "el taxi LLEGÓ veinte minutos tarde y el taxista ERA muy antipático. The taxi driver was unfriendly in the imperfect tense in the same taxi that arrived late in the preterite tense. This is so difficult. 

Can you describe in what general contexts these would be used?

Are they interchangeable or are meanings slightly different depending who you’re talking to? Example such as when talking to children.

The sentence was "watch one of his movies" . I used "mira". The software Use "ve".  Give me a break!!

"Why did you tell Luisa......" seems to me to need the indefinite object pronoun as in "¿Por qué le habéis dicho a Luisa...." but this answer is marked as incorrect. Why? Isn't it actually the correct way to say this part of the sentence even though I haven't gotten to a lesson about these pronouns?

What about the (even in English) problematic decade of 2000-2009? 

or 2010-2019 ?

Hola!

Quiero saber si los personas mexicano dicen "j" para "ll" y "y" o es un "y" sonido? Vivo en California y quiero sonar mas natural para mi comunidad. Gracias por todo!

(Sorry if my Spanish is broken, I just restarted learning)

I'm confused why the answer for #10 is cierto when the translation is "some/a bit" and not "certain." 

Several of my answers in several tests are misrecorded. I answered one way and it says I answered something else. What's going on?

Also, you should have explained that capitalizing, punctuation and accents must be correct. I was marked wrong for not putting a period at the end nd not capitalizing at the beginning. I don't mind but I would like to have known before i took the test.

For the sentence:

Ustedes quisieron reservar en este hotel.

I think I read in one of the lessons that decir was used to describe briefer statements, while contar was used when statements were more extensive or detailed.  Would it also be correct to say "Me contó que solo era cuestión de tiempo..."?