-Are there any tickets left?-Sorry. There are ________, if __________.
______ is known to everybody, Taiwan is a part of China. We must unify it.
—Would you be able to go to the party?
—Are you coming to the English evening? —I'm not sure. I ________ go to the concert instead.
Hearing his words, I couldn't decide ______ or remain.
—This is _________ picture I told you about. —I see. Isn't it ________ beautiful one?