21(2011·山东枣庄高三第一次质检) Provision of food and __________ is their main concern for the flood victims.
A. relief B. safety C. shelter D. defense
22(2010·河南省开封市二模)23.He is neither European, nor American. He is from Australia.
A.a; an; 不填 B.a; an; the
C.a; a; 不填 D.an; an; 不填