6. When an adjective ends in vowel + consonant (wet, big), before -er and -est we

This question is incomplete and requires more context to provide a complete answer. It seems to be asking about a rule related to adding '-er' and '-est' to adjectives that end in a vowel + consonant combination. Typically, in such cases, the consonant is doubled before adding the suffix. For example, 'big' becomes 'bigger' and 'biggest'. More information is needed to accurately complete the sentence.