下列哪项属于月经先期( )
A．偶见月经超前一次
B．月经周期提前4天
C．月经周期提前6天
D．月经周期提前7天以上
E．月经周期提前3天
参考答案：D
— What's the rule in your family?
— My mother doesn't allow _____ in the house and I am allowed _____ for an hour every day. [ ]
A. to smoke, to watch TV
B. smoking, watching TV
C. smoking, to watch TV
D. to smoke, watching TV
（ ）决定教育的发展水平及教育的规模和速度。
A．政治制度
B．经济制度
C．生产力水平
D．科学技术
