A．whoB．whomC．whatD．which

This is the book（)I have learned a lot.A. to whichB. by whomC. from which

A．whoB．whomC．whoseD．whoever

【C16】A．whoB．theyC．thatD．which

【C5】A．whoB．whatC．whomD．which

A．whereB．whomC．which

【C9】A．whichB．whomC．whatD．who