During adolescence--- ______time of life between child and adult, teenagers want to be __________part of the group.
A．a, / B．the, the C．the, / D．a, the
As they ______ their way through the desert the sun beat down upon them with more fierceness.
A．went B．took C．came D．made
The children had only _______ slight temperature, but the doctor regarded the illness as serious enough for ________ hospital treatment.
A．a; 不填 B．不填; the C．a; the D．不填; a
— Can I help myself to something to eat?
— Of course, you are ______ to, you are our guest.
A．required B．requested C．hoped D．expected
People who have studied ancient instruments are hoping to learn more about the culture that ______ this ancient flute.
A．produce B．produced C．is producing D．was produced
Because natural disasters occur at random times, it is difficult to warn people _______.
A．at present B．at last C．on time D．in advance
