题目

They thought       important to look right and left when      the road .       A. it's ,cross        B. it ; to cross     C. it , crossing        D. it was , to cross 答案：C人的一生中身体发育和智力发育的黄金时期是（ ）A. 婴儿期 B. 幼儿期C. 儿童期 D. 青春期