In Persian, almost all the words which can be used as adverbs can be used as adjectives too.
آرام از آنجا رفتم.
حسن خوب درس میخواند.
لیلا عرب است اما فارسی را خوب حرف میزند.
پرندهها قشنگ میخوانند.
I left (lit. went from) there slowly.
Hassan studies well.
Laila is Arab but she speaks Persian well.
The birds sing beautifully.
However, as in English, there are some words that are mainly used as adverbs.
بالاخره او را دیدم.
همه دیر خوابیدند.
اتوبوس زود آمد.
ناگهان درها باز شدند.
مادرم دوباره صدایم کرد.
موبایل امید همیشه خاموش است.
Finally I saw her.
Everybody went to sleep late
The bus came early.
Suddenly the doors opened.
My mother called me again
Omid's mobile is always switched off.
There are also a group of Arabic words which are normally used as adverbs (in fact, they are usually sentence adverbs). They all end with the originally Arabic “tanween” ( اً ) which is pronounced somehow similar to the “an” in the English word “man”.
احتمالاً حسین فردا به لندن بر میگردد.
فرهاد حتماً جوابِ سؤال را میداند.
تکلیفم را بعداً مینویسم.
نگهبانِ این در معمولاً خواب است.
Probably Hossein will return to London tomorrow.
Farhad definitely knows the answer to the question.
I’ll do (lit. write) my homework later.
This door’s guard is usually asleep.
Additionally, here are some examples of cases where these adverbs are used to modify adjectives or other nouns.
جوابِ شما کاملاً درست است.
دیشب دقیقاً ده ساعت خوابیدی!
Your answer is completely right.
Last night, you slept for exactly ten hours.
An adverbial noun group can contain a preposition. The preposition “به”, literally meaning “to”, takes a new meaning in adverbial noun groups, showing the quality of the action of the verb.