涂抹封面胶时,第一遍照灯的时间为()。
A.5~10s
B.10~15s
C.15~20s
D.20~30s
参考答案:D
胆汁中与脂肪消化关系最密切的成分是()
A.胆固醇
B.磷脂酰胆碱(卵磷脂)
C.胆色素
D.胆盐
E.脂肪酸
It rained _______ last Sunday. They had to stay at home.
A. all the day
B. all days
C. the all day
D. all day