Грамматика русского языка. Часть 12. Наречия. Глава 2. Сравнительная и превосходная степень наречий. Russian Grammar. Part 12. Adverbs. Unit 2. Comparative and Superlative Forms of Adverbs.

Adverbs, like adjectives, have comparative and superlative forms (e.g. he runs more quickly and he runs the most quickly).

(a) The comparative adverb is identical to the short form comparative adjective: so, for example: быстрее, more quickly, медленнee, more slowly, лучше, better:

Он всегда работает быстрее, чем я.
He always works more quickly thаn I do.

Adverbs ending in -и form their comparative with более:

Он всегда работает более логически, чем я.
He always works more logically than I do.

Грамматика русского языка. Часть 12. Наречия. Глава 1. Наречия. Russian Grammar. Part 12. Adverbs. Unit 1. Adverbs.

Adverbs describe how things are done (she writes slowly). ln English most end in -Iy. In Russian most adverbs are identical with the neuter short form adiective.

(a)  The most common form of adverb describes how the action of a verb is carried out:

Она медленно пишет. Он быстро бегает.

She writes slowly. He runs quickly.

Note that the adverb is usually placed before the verb. Sometimes it is not 'obvious' that there is a verb being described - i.e. tbeverb to be does not exist in the present tense; but phrases describing the weather, for example, rely on adverbs: Сегодня тепло (it is warm today) - тепло is 'desctibing' how it is.

Урок 7. Учимся употреблять пространственные наречия и предлоги. Lesson 7. Learn to use "spatial" adverbs and prepositions.

The words напротив, впереди/сзади, внутри/снаружи, возле, вокруг are adverbs when used with verbs, and describe the action; when used with nouns in genitive case they are playing the role of prepositions.
But in both cases they serve to express spatial relationships between objects.

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