What is added to form the superlative of an adjective with two syllables?

When forming the superlative of an adjective with two syllables, the correct approach is to use "more" to create the superlative form. This is because two-syllable adjectives can vary in their superlative formation; some take "more" instead of an ending. For instance, "happy" becomes "happier" for the comparative and "most happy" or "happiest" for the superlative depending on the context.

In contrast, adjectives with one syllable typically take the "-est" ending to form the superlative, like "tall" becoming "tallest." The option highlighting "most" would often apply to adjectives that are longer or more complex, not limited to the two-syllable category. Therefore, "more" effectively signifies the comparative degree for two-syllable adjectives, leading to a more accurate understanding of their superlative forms.