How do we form the comparative and superlative degrees of adjectives ending in -ow?

How do we form the comparative and superlative degrees of adjectives ending in -ow?

To form the comparative degree of adjectives ending in -ow, we add -er to the adjective. For example, "narrow" becomes "narrower."

To form the superlative degree of adjectives ending in -ow, we add -est to the adjective. For example, "narrow" becomes "narrowest."