take是及物动词，在句中做谓语，后接交通工具的名词做宾语；by是介词，后接不加冠词的表示交通工具的名词，构成介词短语，在句中做状语。如：I take a bus to work every day.=I go to work by bus every day.
take和by结构上的区别
by+交通工具单数：
交通工具前不能有其他词
take a/the+交通工具：
交通工具前有a或the
by plane搭飞机
take a plane搭飞机
by bus搭公交车
take a bus搭公交车
They will take a bus to the airport.
=They will go to the airport by bus.
他们将会搭公交车去机场。
Many people take the bus to the museum.
许多人乘这趟公交车去博物馆。