It only says "We can also form the superlative of some adverbs with the suffix -ísimo", but not which ones these are.
There's something on cerca & lejos, but how about other irregular adverbs (those having an independant form, like bien)?
It seems these would not have any -ísimo from, as I neither found "lo hiciste bienísimo" nor "lo hiciste buenísimo", but solely "lo hiciste muy bien".
Hola Cinzia
As you pointed out this superlative doesn't work with bien (bienísimo would be incorrect)
Apart from the adverbs that we mention in the lesson, this also applies to quantity adverbs poco and mucho, so, for example:
Bebe muchísimo y come poquísimo.
She drinks a lot and eats very little.
Saludos
Inma
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