I still don't understand when we have to use DE or HET... :(
There is is not much to understand about it, there are a few rules, but mostly it's a matter of learning if a noun is a de woord or a het woord. See this elaborate explanation.
Singular: Common gender nouns take De, neutral take Het. Plural: Everything takes De.
why "duur" and not"dure"
Because the adjective is in predicative position (i.e.: after a copulative verb -here, is)
I have seen "duur" and "dure" both used, and so I thought since "soep" is a "de" word, it would get "dure", but it said the correct answer uses "duur"? Don't "de" words get the "e" ending?
That's when the adjective is placed before the noun.
When used predicatively, adjectives don't get the extra e at the end.
Kostbaar is Precious or Valuable. Duur is just Expensive. (Online dictionary.)
What is the difference between duur and kostbaar?
See PaCa's comment above.
You could have seen that i was stil bizzy! !!!!!!!