Ellos = they(all males or males and females) ,Ellos escriben. Ellas = they(all females) Ellas escriben. Tú = you, Tú escribes Usted = you (formal), Usted escribe. Ustedes = you all (plural of you) , Ustedes escriben. The verb escribir(to write) is conjugated with the pronouns to yeild all those varations(escriben, escribes, escribe). And the words alone can be used without a pronoun before them. Escriben = They write. You all write. You write. Escribes = You write. Escribe = He writes. She writes. You write.
'Escribes' implies 'you'. Note that this is the informal 'tu (you)'. The formal you, which is 'usted', is conjugated as 'escribe' for the verb 'escribir'. Escribir is a regular -IR (ending in -ir) verb. Here are the conjugations for this verb and it's types. Simply remove the -ir and put on the new ending, as shown below. -IR Conjugations with 'Escribir' as Example: Yo (I) - '-o' (escribo) Tu (informal you) - '-es' (escribes) Usted (formal you) - '-e' (escribe) El (he) - '-e' (escribe) Ella (she) - '-e' (escribe) Nosotros (we) - '-imos' (escribimos) Vostros (you all, SPAIN ONLY) - '-ís' (escribís) Ustedes (you all, they) - '-en' (escriben) Ellos (you all, they [male only or mix]) - '-en' (escriben) Ellas (you all, they [female only] - '-en' (escriben) From this, maybe you can see why you generally use the pronoun for the el/ella/usted and ellos/ellas/ustedes form until the subject has clearly been identified. Also, please note that these conjugations are just for REGULAR -ir verbs, and not all. However, if you do not know whether a verb is regular or irregular (and that is something you just have to memorize about each specific verb), always assume it is regular- the majority of verbs are. In closing, I hope my explanation helped you. If it did, please click that up arrow below this post. I have not copied this of some site, and have spent my own time writing this out. Thanks. --Impostura One
A really helpful tool if you don't understand the conjugation.
I like using for verbs http://conjugador.reverso.net/conjugacion-espanol-verbo-escribir.html
Like in English, you can categorize pronouns as 1st/2nd/3rd person, and singular/plural (one person, or more than one).
1st person refers to the speaker. In English, the singular is "I" and the plural is "we". In Spanish, the singular is "yo" and the plural is "nosotros/nosotras".
2nd person refers to the listener. In English, both singular and plural are "you" (though we sometimes say "you all" or "you guys", etc. to specify that it's plural. In Spanish, there are familiar and polite forms. "Tú" is the singular familiar form, to use with a friend. "Usted" is the singular polite form. In Spain, the plural of "tú" is "vosotros" and of "usted" is "ustedes", but in Latin America, both go to "ustedes".
3rd person refers to someone else. In English, singular is "he/she" and plural is "they". In Spanish, singular is "él/ella" and plural is "ellos/ellas".
Ellos escriben is for when it's all men or men and women who write, ellas escriben is for when it's all women, and ustedes is you all in general. Usteded is both man and female. usted is the formal version of tu, you would use it for a teacher or an elder rather than a friend. Thank you high school spanish :)
Ustedes is "You (plural)". If I'm a teacher addressing my students I would say, "You need to open your books to page 113." Ellos is used to describe a large group of people indirectly (not speaking directly to them). If I'm addressing a fellow teacher I would say that, "They need to open their books to page 113". If even one male is in the group, I would use "ellos". If the group is entirely female (zero men), I would use "ellas". Usted is the formal "you" used when the subject is singular; i.e. if I'm addressing my boss I would say, "You asked me to have the students read page 113". Tú is the informal "you" used when addressing a friend or someone of the same or lesser social status. I would use this when addressing one student in the front of class saying, "You need to open your book to page 113", or when addressing a fellow teacher, "You need to have them student page 113."
You are sort of close, but no seegar. You are right that just like in English, you don't put two conjugated verbs together; you put a verb and a gerund. "Yo soy escribiendo" "I am writing." Caution: there are two forms of "to be:" estar and ser. They are used to convey different senses of being. You'll get into them soon enough, but estar (Yo estoy escibiendo) would actually be the one you want in this case.