题干
My grandfather was badly ill, so we asked him _________ smoking.
A：to give up
B：give up
C：gave up
D：given up
答案(点此获取答案解析）
A
My grandfather was badly ill, so we asked him _________ smoking.
A：to give up
B：give up
C：gave up
D：given up
C（s）＋4D（g）＋Q，右图中a、b表示一定条件下，D的体积分数随时间t的变化情况。若要使曲线b变为曲线a，可采取的措施是：①增大B的浓度 ②升高反应温度 ③缩小反应容器的体积（加压） ④加入催化剂( )