He spent too much time talking on ______ phone while we were all busy at _____ work.
A．the, 不填 B．a, 不填
C．不填, 不填 D．the, the
As is known to us all, _____ tiger is in _____ danger of becoming extinct.
A．the, a B．the, 不填
C．a, 不填 D．不填, the
This is _____ best kind of _____ pen you can get here.
A．the, the B．the, a
C．the, 不填 D．a, the
How strange! These years my birthday always falls _____.
A．on the Sunday B．on a Sunday
C．on Sunday D．at a Sunday
As _____ writer, he was _____ complete failure.
A．a, a B．a, the
C．不填，不填 D．a, 不填
The operation is _____ success and the patient is now out of _____ danger.
A．a, the B．a, 不填
C．不填, the D．不填，不填
