Questions & Answers about Blóðið er rautt.
-ið is the definite article attached to the end of the noun. Icelandic usually puts the onto the noun instead of using a separate word like English.
So:
- blóð = blood
- blóðið = the blood
In this sentence, -ið is the neuter singular definite ending.
That is a normal feature of Icelandic grammar. The definite article is usually a suffix, not a separate word.
So instead of English:
- the blood
Icelandic normally says:
- blóðið
You will see this all the time in Icelandic:
- hús = house
- húsið = the house
Er is the present tense, 3rd person singular form of vera (to be).
Because blóðið is singular, Icelandic uses singular er:
- ég er = I am
- þú ert = you are
- hann / hún / það er = he / she / it is
So Blóðið er rautt follows the same basic pattern as English X is Y.