-지만

음식이 맛있지만 비싸요.
The food is delicious but expensive.

음식이 맵지만 맛있어요.
The food is spicy but delicious.

매웠지만 맛있었어요
It was spicy but delicious.

간식이 맛있지만 양이 적어요.
The snack is delicious but small in quantity.

간식이 건강하지만 맛없어요.

->a grammatically correct sentence. but it's little bit strange. if you want to say 'the snack is good for health', write [건강하지만->건강에 좋지만(good for health but..)]

The snack is healthy but not tasty.

무궁화가 싸지만 느려요.
Mugunghwa is cheap but slow.

KTX 빠르지만 비싸요. -> KTX(는) 빠르지만 비싸요
KTX is fast but expensive.

영화가 신나는지만 이상해요.
The movie is exciting but strange.

제 집이 가깝지만 작아요.
My home is close but small.

카페가 좋았지만 여기서 멀어요 ->카페는 좋았지만 여기서 멀어요. [~았다(past tense)]
The cafe is good but far from here.

goodjob! :) everything makes sense!