It's a useful introduction to an extremely complex subject.

　　這是對一門極為復雜的學科的有益入門教程。

　　This album was my first introduction to modern jazz.

　　這張專輯唱片讓我初次接觸了現代爵士樂。

　　The introduction of a new tax accounted in no small measure for the downfall of the government.

　　這屆政府的垮臺在很大程度上歸因于征收一種新稅。

　　The introduction of a new code of criminal procedure has also slowed up the system.

　　新刑事訴訟法的.出臺也使系統的效率有所降低。

　　Michael Jackson, of course, needs no introduction.

　　邁克爾·杰克遜，當然，眾所周知。