Adverbs modify verbs, adjectives, other adverbs, or whole sentences. They often answer how, when, where, how often, how much, or to what extent. Understanding what the adverb modifies helps you choose the right form and position.

The most common way to form an adverb from an adjective is to add -ly. This usually keeps the adjective’s meaning and turns it into “in a … way.” Not all adverbs use -ly, and not all -ly words are adverbs.

Word/Phrase	Definition	Example
quick → quickly	in a quick way	She answered quickly.
careful → carefully	in a careful way	Drive carefully.
recent → recently	not long ago	I recently moved.
usual → usually	in the normal way most times	He usually walks.

When adding -ly, spelling sometimes changes to keep pronunciation and standard spelling patterns. Learn the common transformations so you can form adverbs correctly from a wide range of adjectives.

Rule	Example
Most adjectives add -ly directly	slow → slowly
Adjectives ending in -y change y to i + -ly	easy → easily
Adjectives ending in -le often change -le to -ly	gentle → gently
Adjectives ending in -ic usually add -ally	basic → basically
True takes -ly as truly with a spelling change	true → truly

Some adjectives already end in -ly and are usually not turned into adverbs with another -ly. In these cases, English often uses a different adverb form or a phrase like in a … way to express the meaning.

Rule	Example
Many -ly adjectives do not become *-lily	friendly → in a friendly way
Some -ly adjectives use a different adverb	good → well
If no standard adverb exists, use a prepositional phrase	costly → at a high cost

Some adverbs have the same form as adjectives and do not take -ly. These are common in everyday English and are often required after certain verbs or in fixed expressions.

Word/Phrase	Definition	Example
fast	quickly	He runs fast.
hard	with a lot of effort	She works hard.
late	after the expected time	They arrived late.
early	before the expected time	I woke up early.
straight	in a direct line	Go straight ahead.

Some pairs exist where the flat form and the -ly form are both possible but differ in meaning or style. Learning these contrasts prevents confusion because the -ly form is not always just “the adverb version.”

Rule	Example
hard is effort, hardly is almost not	I work hard. / I hardly work.
late is timing, lately is recently	She arrived late. / Lately, she has been busy.
near is distance, nearly is almost	The store is near. / I nearly fell.
high is physical height, highly is very or greatly	The plane flew high. / It is highly likely.

Many adverbs express degree or intensity rather than manner. These often modify adjectives or other adverbs and include both -ly and non--ly forms. Choosing a degree adverb depends on strength and whether the adjective is gradable.

Word/Phrase	Definition	Example
very	strong intensifier for gradable adjectives	very tired
really	strong intensifier, informal to neutral	really important
quite	medium intensity, meaning depends on context	quite good
extremely	very strong intensifier	extremely cold
too	more than acceptable or needed	too loud

Some adverbs comment on the whole sentence rather than one word, expressing attitude, certainty, or connection. These often appear at the beginning of the sentence, but can also appear mid-sentence with commas depending on style.

Word/Phrase	Definition	Example
fortunately	expresses a positive outcome	Fortunately, no one was hurt.
honestly	signals truthfulness or emphasis	Honestly, I forgot.
probably	shows likelihood	She will probably agree.
however	shows contrast between ideas	However, we decided to wait.

Adverb placement depends on what the adverb modifies and what type it is. Manner adverbs often appear after the verb or object, frequency adverbs often appear before the main verb, and sentence adverbs often come first. Position can change emphasis and sometimes meaning.

Rule	Example
Frequency adverbs usually go before the main verb	She often studies.
Frequency adverbs go after be	He is always late.
Manner adverbs often go after the object	She read the email carefully.
Sentence adverbs often go at the start with a comma	Unfortunately, it rained.

Choosing between an adjective and an adverb depends on whether you are describing a noun or describing an action or quality. After linking verbs like be, seem, and feel, English typically uses an adjective rather than an adverb. This helps avoid errors like using *quickly to describe a subject state.

Rule	Example
Use adjectives to modify nouns	a quiet room
Use adverbs to modify verbs	Speak quietly.
After linking verbs, use an adjective	She feels tired.
Use adverbs to modify adjectives or adverbs	incredibly fast