How long will basic words pursue me?
I'am learning with Duo for about 3 monthes and completed halves of my courses. And the first several skills seem to be permanent gold. Still I continue to get words from basic vocabulary.
I really feel like I was born with built-in knowledge of how the horse/pferd/cheval/caballo eats/frisst/mange/come that осточертелое apple/Apfel/pomme/manzana.
Will they continue to appear until the end?
Cam (waves) is correct that the basic words will still appear from time to time in your reviews. However, as you add more vocabulary they will pop up less frequently as newer words are being reinforced. You also have the option of strengthening words in a particular category, if you prefer, rather than all of the words. Click on a topic and there is an option to just strengthen words/review words within that topic. Good luck!
Depending on the course (and for most of the courses anyway), yes. They want to add as much reinforcement of the words as possible, so you will ofttimes be seeing "horse" in your sentences, for example. The only course (so far) that I have found is especially different is the Dutch course, as the very last two skills are about cultural stuff: locations and different kinds of food, drink, and venders. So you spend more time talking about Groeningen than horses and apples (except for "appelflappen" =) ).