Language: adverbs

You might know, adverbs are often formed with 'ly'.

He walked quickly.
He looked hungrily at the hamburger.
She felt quietly confident.

However, there are many exceptions, and here are two important ones:

X I worked lately.
X I worked hardly.

The adverb of 'late' is 'late. 'I worked late' is correct. 'Lately' is a different word and means 'recently'.

The adverb of 'hard' is 'hard'. 'I worked hard' is correct. 'Hardly' is a different word and means 'not much; very little'. In fact, 'I worked hard' and 'I hardly worked' have opposite meanings!