Kau (romaji)

Ototoi, mise ni ikimashita. Choko o kaimashita/ katta. Yasai o kaimasen deshita/ kawanakatta (past tense). Ashita, mise ni ikimasu. Yasai o kaitai.

How do you say "Tomorrow I want to go to the store to buy vegetables?"

Ashita yasai o kaini mise ni ikitai (or ikitai desu) kaini=to buy.