'Wo?' describes where something is. It can e.g. be answered with: - in der Post / Apotheke ( = inside) - bei der Post / Apotheke ( = next to, beside) - vor der Post / Apotheke ( = in front of) - auf der Post / Apotheke ( = on, but only a bird can sit there :-)) 'Wohin?' describes where something is moving to. This can be answered with: - zur Post / Apotheke ( = to) - in die Post / Apotheke ( = into) - auf die Post ( = onto, the bird) - nach Berlin ( = to, but only with cities) hope that this can help you