V+ 을/ㄹ 때마다 V/A+ 더라고요.

It is used to tell the listener what the speaker has learned from repeated experiences.

For ‘-을/ㄹ 때마다’, if the stem of an action verb ends with a vowel or ‘ㄹ’, you use ‘-ㄹ 때마다’, with another consonant, you should use ‘-을 때마다’.

‘-더라고요’ is used attached to the stem of an action verb or a descriptive verb.

이 길은 다닐 때마다 막히더라고요.
This road gets congested every time I go.

내 동생은 식사를 할 때마다 식탁에 음식을 흘리더라고요.
My brother spills food on the table every time he eats.

명동은 갈 때마다 복잡하더라고요.
Every time I went to Myeong-dong, it was complicated.

Conversation:

어서 오세요. 어떤 구두를 찾으세요?
Welcome. What shoes are you looking for?

제가 지금 입고 있는 정장에 잘 어울리는 구두를 좀 보고 싶은데요.
I’d like to see some shoes that go well with the suit I’m wearing now.

정장이 일반적인 스타일이니까 무늬나 장식이 없는 구두가 어때요?
How about shoes without patterns or decorations since your suits are a common style?

음…. 그건 좀 밋밋해 보이지 않을까요?
Well, don’t you think it will look a little plain?

그러시면 구두 앞코 부분에 무늬가 좀 들어가 있는 것을 보여 드릴까요?
Then, would you like me to show you shoes with some pattern on the front nose?

그게 좋겠네요. 그리고 발이 편하면 좋겠어요.
That would be nice. And I hope my feet will feel comfortable.

지금 신고 있는 구두는 오래 걸어 다닐 때마다 발뒤꿈치가 까지더라고요.
I get my heels grazed if I walk for a long time with these shoes I’m wearing.

가죽이 딱딱해서 그래요. 이 제품은 가죽을 부드럽게 가공한 거라서 편하실 거예요.
It’s because the leather is hard. You will feel comfortable with this product because it is made of softened leather.

Related words
밋밋하다 to be plain
(구두) 앞코 (shoes)front nose
발뒤꿈치 the heel
까지다 to be grazed

Source: Yonsei University. Korean Language Institute