单项选择题
A．yet B．still C．probably D．also
A．would be little better than the fourth level B．may be a lot more desirable than the first four C．can be the last and most satisfying level D．will become attainable before the government takes actions
A．Six Stages for Repairing Sam’s Bicycle. B．Possible Steps of Problem-solving. C．Necessities of Problem Analysis. D．Importance of Analyzing a Problem.