The phrase "lay an impost" refers to imposing a tax or duty on something. It is important to note that "impost" is not spelled how it sounds. The correct spelling is i-m-p-o-s-t. The IPA phonetic transcription for "impost" is /ˈɪmpoʊst/. The "i" is pronounced as "ih", the "m" as "m", the "p" as "p", the "o" as "ow", the "s" as "s", and the "t" as "t". Spelling can be tricky, but with practice and attention to detail, it can be mastered.