The Little Words

Very often, it's not the important, big words of a language which are lacking in a non-native's vocabulary. After some time, it's easy to discuss God, work, and Schopenhauer in a foreign language. No, it's the little words you aren't taught in school.
Or how to express the idea of "Ich habe mir diese Tassen bei Jacobs ertrunken" in any other language but German?