Ich warte an der Ampel.

I

Breakdown of Ich warte an der Ampel.

• warten: to wait
• die Ampel: the traffic light
• an: about

Questions & Answers about Ich warte an der Ampel.

Why is it an der Ampel and not something like bei der Ampel or auf der Ampel?

In German, an is the normal preposition for being at a vertical object or boundary, like a wall, door, or traffic light.

• an der Ampel = at the traffic light (standing next to it / at that spot in the street)
• bei der Ampel = near the traffic light, in the area of the light (more general, “nearby”)
• auf der Ampel would literally mean on top of the traffic light (physically on it), so that’s wrong here.

So Ich warte an der Ampel is the idiomatic way to say you are standing at that traffic light and waiting there.

Why is it der Ampel and not die Ampel if the noun is feminine?

The basic (nominative) form of the noun is:

• die Ampel = the traffic light (feminine)

But an is a two-way preposition (Wechselpräposition).
For location (where you are), it takes the dative case.

Feminine noun in dative singular:

• die Ampel → der Ampel

So:

• Nominative: Die Ampel ist rot.
• Dative (location): Ich warte an der Ampel.

You see der here not because the noun is masculine, but because it’s feminine dative.

Why is it an der Ampel and not an die Ampel?