I've been wondering if there are definite rules as to whether one adds a "de" sometimes, but sometimes I go awry with an incorrect guess. At present it seems to me that a noun after the second "de" is safe enough. Am I right? The help from the quick lessons is immensely helpful, but thus far I haven't found one which would solve my problem with rules for the 'De's'.
Clive
Your hunch is correct: you need the additional de when you're speaking of some "stuff" (noun). Without de it is about a property (adjective).
Il y a de moins en moins de lait dans lefrigo. -- There is less and less milk in the fridge.
Il fait de plus en plus chaud. -- It's getting hotter and hotter.
Always 'de moins/plus en moins/plus de NOUN'.
Note that the nominal expression 'De moins(plus) en moins(plus) de NOUN' can be placed at the start of a sentence. (Example in lesson)
This is effectively an expression of 'quantity of something' and uses 'de..' as do other expressions of quantity - eg beaucoup de NOUN, trop de NOUN, la plupart de NOUN.
When followed by adjectives or adverbs it is ' de moins(plus) en moins(plus) ...ADVERB/ADJECTIVE' .
A different word order with verb comparison - the verb precedes the comparative phrase to become ' VERB ..... de moins/plus en moins/plus. '
Note that ' de moins/plus en moins/plus .. ' cannot be placed directly at the start of a sentence (Attention point in lesson)
The lesson below is linked in the lesson you have referred to - combined, they cover the 'rules' :
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