1. at; in
indicates location of action; にて is the formal literary form
2. at; when
indicates time of action
3. by; with
indicates means of action
4. and then; so
5. and; then
indicates continuing action; alternative form of 〜て used for some verb types
when read as "で"
6. let me tell you; don't you know
at sentence-end; indicates certainty, emphasis, etc.
when read as "で"