一Don't worry about your trip to the US. I'll be with you all the way.
一OK. Thank you. It'll be my first time to travel abroad.
A:from beginning to end
B:on the way
C:in the way
最后一段在全文中起到____作用,与第一段是____的关系。
同学们依据此图片获得数据,如下表:
手持一个凸透镜在室内白墙和窗户之间移动(离墙更近些),在墙上能看到
① 蚕豆的雄蕊
② 桃花的雌蕊
③ 蝗虫的精巢
④ 小鼠的卵巢