Questions & Answers about Mig dreymdi þennan stóra líka!
Why does the sentence start with the accusative mig instead of ég?
The verb dreyma (to dream) is one of the verbs that takes a quirky subject. Instead of the dreamer being in the nominative case like a normal subject, it must be in the accusative case. Because the subject is accusative, the verb doesn't conjugate to match the speaker; it stays in the third-person singular form, which is dreymdi in the past tense.
Why is the thing being dreamt about (þennan stóra) also in the accusative case?
The verb dreyma is unusual because it takes a double accusative. Both the person experiencing the dream (mig) and the thing being dreamt about (þennan stóra) are put into the accusative case. Notice that you also don't need an extra preposition like about to connect them.
Why does the adjective stór have the ending -a in stóra here?
Because it follows the demonstrative word þennan (this), the adjective must use its weak declension. For a masculine word in the accusative case, the weak ending is -a, making it stóra.
Where is the word for one in the Icelandic sentence?
In English we use the placeholder word one to say this big one, but in Icelandic you don't need it. You can just use the adjective stóra on its own to stand in for the noun.