The comparative form of an adjective takes the ending -er.
in the same way: arg, alt, arm, hart, krank, lang, nah, scharf, schwach, schwarz, stark, grob, groß, hoch.
Attention! The last consonant is never doubled (compare: English: big – bigger – biggest, but German: schmal – schmäler – schmälst-).
There are some adjectives which have no comparative or superlative forms, such as tot (dead), lebend (alive). The same applies to most of the participles: geschrieben (written), gelesen (read), gegessen (eaten).
Dieses Haus ist das schönste.
Dieses Haus ist am schönsten.
Dieses Haus ist so hoch wie das andere – This house is as high as the other.
Dein Haus ist höher als meines – Your house is higher than mine.
Adverbs can be compared in the same way as adjectives.