Can some of you suggest some basic Spanish books for beginners?
I have completed the tree. I can understand the sentences. I want to learn more in Spanish. Suggest ways to improve. Is there a good book on Spanish grammar? Storybooks? novels? etc. Plz suggest.
You can try with this simplified version of "Lazarillo from Tormes" a well-know spanish tale written in the XVI century. There are eight chapters on it, you can ask for a dictionary if you found some words you don't know, it is a synthethic version but wonderful for Spanish begginer. ¡Buena suerte y disfrute su lectura! ;-) http://www.elhuevodechocolate.com/cuentos/lazaro1.htm
Whatever you choose to read, I highly recommend using a Kindle (regular Kindle or PaperWhite, not a Kindle app or a Kindle Fire) with a foreign-language dictionary installed, if you can afford it. https://gregreflects.blogspot.com/2014/09/how-to-read-foreign-novel-on-kindle.html
You can browse Amazon's "foreign language" books and select books for juveniles. Some of them are quite reasonable.
Cajas de Cartón is frequently recommended. It's used in a Spanish class at my school. I've not read it myself, but it's on my list.
if you are looking for easy storybooks, I recommend Elephant and Piggie, Dr Seuss, or any children's books in Spanish. They can actually really help :) you can probably find them at your local library, and if you want something a bit harder, they also have some chapter books in Spanish at most libraries.
The author Paco Ardit has a series of ability-leveled Spanish novels available on Amazon. They are quite interesting with plots and characters appealing to adults. The titles progress smoothly from elementary to advanced levels with increasingly longer, more complex sentences and greater use of more abstract vocabulary.
Bar none the best is a text-book / work-book Complete Spanish Step-by-Step https://www.amazon.com/Complete-Spanish-Step-Barbara-Bregstein/dp/1259643417/ref=sr_1_1?ie=UTF8&qid=1528846325&sr=8-1&keywords=complete+spanish+step (not an affiliate link) for only $17, has 556 pages
Skim it first, then go back and start working on it. You can write in it, but I use a separate notebook.
First book I read after completing the Duolingo spanish tree was "El curioso incidente del perro a medianoche". From what I learned on Duolingo and memrise, it was still a challenge, but i really enjoyed it.
Actually I tried several novels and was just lost and frustrated. A good piece of advice is to try the sample chapters on Google play and Amazon to see if it is something you can read and/or will enjoy. (Don't try "cien años de soledad"! Read a few before trying that! Hehe)
The Sarah and Duck books don't seem to be available as Spanish books, but there are Sara y Pato videos on Netflix and YouTube.
There are Richard Scarry books in Spanish. Look at Amazon, and then look at other books that Amazon suggests.
GoComics.com has a substantial collection of comic strips in Spanish.