于是

thereupon / as a result / consequently / thus / hence

to go / to take / sentence-final interrogative particle / variant of 於|于[yu2]

(of time or place) in; at; on / (indicating any indirect relation) to; toward; vis-à-vis; with regard to; for / (indicating a source) from; out of / (used in comparison) than / (used in the passive voice) by

variant of 是[shi4] / (used in given names)

to be (followed by substantives only) / correct; right; true / (respectful acknowledgement of a command) very well / (adverb for emphatic assertion)