According to my observation, there are at least two types of using "Not that....". And my question is: what does "not that" mean in its second type of usage?
In the first usage, "not that" is followed by a structure-complete sentence or expression.
I've been teetering down my twittering and self editing my Facebooking lately. It's not that I don't have the urge to write things. It's just I have to fight the urge to write really inappropriate things that maybe my old High School English teacher doesn't really need or want to know.
It’s not that I don’t care about football. I just don’t care enough.
In the second usage, "not that" is followed by an object-missing expression.
Example 3 (from Fringe):
Olivia: Anything to do with metamorphic ability? Peter: Not that I can tell.
Here, tell is a transitive verb and its object is missing.
Example 4 (from Fringe):
Olivia: Were you involved in...? Walter: Not that I recall.
Here, recall is a transitive verb and its object is missing.
I understand that, in the first usage, "not that" sort of means "it doesn't mean...". But I'm not sure, in the second usage:
- Why are objects of transitive verbs missing?
- What does this type of "not that..." sentences mean here?