Learn Hardcore German: Mein Freund ist heute nervös.

Because Freund is masculine and in the nominative case. In German, mein is the correct masculine nominative form, while meine is used for feminine or plural nouns.

Why is Freund capitalized?

In German, all nouns are capitalized regardless of their position in a sentence. Freund is a noun, so it must start with a capital letter.

Why does ist come right after the subject?

German typically places the conjugated verb in the second position in a main clause. Here, Mein Freund is the subject (first position), and ist is the verb (second position).

Does nervös mean the same as the English 'nervous'?

Yes, nervös usually translates to 'nervous.' It can also carry the meaning of feeling anxious or on edge, similar to English.

When should I include heute in the sentence?

Include heute if you specifically want to indicate that this mood or condition applies today. You can also omit it if the exact time frame isn’t important.