"Would" has many meanings, and "used to" has two primary meanings - (1) "did something habitually in the past," or when you add a "to be" verb, it means that (2) you are accustomed to something. Example for (1): I used to go to church every Sunday when I was living in Boston. Example for (2): I'm used to the cold in Minnesota. One of the meanings of "would" is the same as (1) above. So you can say "I would go to church every Sunday when I was living in Boston." to replace (1) above. When "would" is used in one of its many other meanings, it is not the same as "used to." (3) "Would you like to have some coffee?" cannot be replaced by "Used to you like to have some coffee?" (4) "I would have gone to see her if I had the time" cannot be rewritten as "I used to have gone to see her if I had the time." Only in the specific context when you are referring to a habitual action that happened in the past can you use "would" and "used to" more or less interchangeably.

Ok, would is for a invitation, or hypothetical situations (wishes) for example: -Would you like to drink a coffee? -I would be better student. "Used to", is for habits in the past (something that you did in the past and now you don't do it) -I used to play in the park, when i was a child. -Do you used to play the guitar?

as i know would=used to he used to read a lot of book when he studied at the college. he would read a lot of book when he studied at the college.

i am not native speaking and for sure i can be wrong but in american english school i studied we learned that would use instead of used to. more examples: do you know who the Bradley twins are? yes, they are the ones whose parents would dress them alike whenever they went outside=yes, they are the ones whose parents used to dress them alike whenever they went outside. (same meaning)

i can answer your question , " used to " \" didn't used to '" + infinitive verb to talk about states or repeated actions in the past , For example : i used to want to be a doctor , but now i want to be a teacher . we used to go on a holiday every summer . Use " would " + infinitive verb to talk about repeated habits in the past ( not a states ) . for example : Every afternoon , my friends and i would talk for hours on the phone . After dinner , Grandfather would sit and tell us all stories from long ago . Rasha