The smoggy weather has made us realize ________ terrible problems we are faced with.
Some exercises appear to be ______ ones you have done, but on ______ second thoughts, you’ll find that they’re different.
. —Thank you for having bought me a ticket for the World Expo in Shanghai!— ________.
.—Did he _______ to escape being punished by the police? —No, he _______ to, but failed.
._______ in the leg, the soldier was sent to hospital.
Tony was very unhappy for _______ to the party.