OK, next question from me. First of all, I homeschool my 17 year old son and we're both learning German using Rosetta Stone and supplementing with Duolingo. Neither teach much about grammar so I went to Barnes & Noble and bought a German grammar book. We're studying negation in it right now and one of the rules is "Following the verb "haben" place "nicht" after the object of the verb. I understand that perfectly. Then we get to the worksheets and there are some questions that we're to write two sentences in answer to, one beginning with "ja" and the other beginning with "nein" and using either "kein/keine" or "nicht" to negate the question. The first question using "haben" is Hast du das Kleid? My answer (correct according to the answer key) was Nein, ich habe das Kleid nicht. That followed the rule they stated. Then I get to Habt ihr Zeit? So I followed the rule and said Nein, wir haben Zeit nicht but the answer key said it should be Nein, wir haben keine Zeit. Why? Is it because Zeit isn't a concrete noun and Kleid is? I need to get this straight in my mind so I can help my son understand it.
You came across another topic here. It has nothing to do with the position of the "nicht", but with not using "nicht" at all, but a form of "kein" instead. The general rule here is that you use "kein" for the negation of nouns that either are qualified by an indefinite article (a form of "ein") or don't have an article at all. In contrast to that nouns qualified by a definite article (a form of "der/die/das") are negated by using "nicht". You can think of it as "kein" being a translation of "not a" or "not any". Examples: "Ich habe das Kleid" -> "Ich habe das Kleid nicht". "Ich habe ein Kleid" -> "Ich habe kein Kleid". "Ich habe Milch" -> "Ich habe keine Milch". There are lots of further discussions about this topic around here. Simply browse for "kein".
Indeed what fehrerdef said above is what you encountered. When negating a noun that has a definite article, kein is not used.
For more information on this, I suggest reading the following webpages:
Thank you. The lesson was covering when to use kein/keine vs when to use nicht and also where to put nicht in the sentence if using it. I got hung up on the rule for haben but I guess before looking at the verb I need to look at the noun and article. That helps me a lot - thanks again.