在社会主义市场经济中,当经济出现衰退时,政府实行赤字财政政策就能促进国民经济的发展。 ( )
参考答案:错
He ____ angry because he ____ for a long time.[ ]
A.had got; had waited
B.got; waited
C.had got; waited
D.got; had waited
简述注射压力的作用及其选择原则。