如果介词短语放在句首,那么像including这类词后面的谓语怎么办

include这个词有3种用法,简单的说:
动词 Price $10, includes postage.
形容词 Price $10, postage included.
介词 Price $10,including postage.

including后面的动词如果是ing形式的话那它是做动名词用了。这要具体看情况。

including 是由现在分词转换成的介词.既然是介词,后面只能跟名词或代词,不可能跟谓语动词.如:
We are all here including Tom.
Including Tom I have five friends.