_______is this pen?

It was at this time ____ he adopted the pen name “Mark Twain”.A: whenB: thatC: at whic

"Can I borrow your pen？"______"You have a pen."A．is inconsistent withB．entailsC．is contrad

Liu Xiang is ______ this season.

-- Is this your shoe? – Yes it is but where is ________?

This MP3 is ______ that one.

The pen ______he is writing is mine. A.with which B.in which C.on which D.by which