In this unit I learnt… We learnt about... Nouns, Adverb, Adjective, Pronoun, Preposition, Conjunction, And... Adverbs.
A grammatical construction is to with parts of speech.
In parts of speech, I already knew what… A Noun is, and what a Adverb is and that is about all I knew.
The ones I didn’t know were... Conjunction that well and one of the most ones I did't know that well was Adjective.