Ég afhendi vöruna í dag, en endurgreiðslan kemur venjulega innan viku.

I hand in the item today, but the refund usually comes within a week.

Breakdown of Ég afhendi vöruna í dag, en endurgreiðslan kemur venjulega innan viku.

• ég: I
• koma: to come
• en: but
• vikan: the week

Questions & Answers about Ég afhendi vöruna í dag, en endurgreiðslan kemur venjulega innan viku.

Why is it Ég afhendi and not Ég afhenda?

Because Icelandic verbs change with person and number. The infinitive is að afhenda (to deliver/hand over). In present tense, 1st person singular is ég afhendi (I deliver / I am handing over).
(Other forms: þú afhendir, hann/hún afhendir, við afhendum, þið afhendir, þeir/þær/þau afhenda.)

What nuance does afhenda have—does it mean deliver, hand over, or something else?

Afhenda typically means to hand over / deliver (officially or as part of a transaction)—often used in business, shipping, or formal contexts. It implies completing a transfer to the recipient. In everyday speech you might also see skila (return/hand back) or láta (let/give), depending on context, but afhenda is very common for “deliver the product.”

Why is it vöruna and not vara or vöru?

Vöruna is:

• vöru = the noun vara (product/good) in accusative singular
• -na = the definite article attached to the noun (the)

So Ég afhendi vöruna literally means I deliver the product (specific/known one).
If it were indefinite: Ég afhendi vöru = I deliver (some) product/goods (less common in this exact meaning unless you mean goods in general).

How do I know is accusative—what is making it accusative?