Speaking of transitive verbs, set and sit is another that trips people up. Set is transitive it describes an action being done to an object. ie; I set the plant on the table. If "on the table" was omitted from the sentence, it becomes unclear.
On the other hand Sit is intransitive. It describes an action undertaken by the subject of the sentence. I"to sit" does not express the kind of action that can be DONE TO anything. ie; Max sits there ever day. He sat there yesterday, and will be sitting there tomorrow.
I try to remember by thinking, you set objects down, and people and animals sit
reference Get It Write: http://www.getitwriteonline.com/archive/060602SitSet.htm