Learn French: J'ai mal au cou ce matin. - My neck hurts this morning.

In French, physical pain is almost always expressed using the construction avoir mal à (literally, to have pain at). While it is sometimes possible to use the verb faire mal, avoir mal à is the most natural and common way to describe a personal ache.

Why does it say au cou instead of using a possessive like à mon cou?

When talking about body parts, French usually prefers definite articles like le, la, or les rather than possessive adjectives like mon or ton when context makes it obvious whose body part is involved. Since you started with J'ai, it is already clear that it is your own neck.

Where does the word au come from in au cou?

The expression avoir mal à requires the preposition à. Because the word for neck (cou) is masculine, it takes the definite article le. In French, à and le must always contract into au.

Why is it ce matin instead of cet matin or cette matin?