有人认为:()和()的发明比20世纪出现的高爆弹、飞机、坦克对当代产生的影响还大。
参考答案:来复枪;圆锥形子弹
Directions:
A. Study the following picture carefully and write an essay in no less than 160-200 words.
B. Your essay must be written clearly on ANSWER SHEET 2.
C. Your essay should meet the requirements below:
1) Describe the picture
2) interpret its meaning, and
3) give your comments.
关于活鲫鱼的鳃,错误的一项是( )
A.鳃盖在外面,起保护作用,是呼吸的主要结构
B.鳃丝既多又细
C.鳃是鲜红色的
D.鳃的主要作用是吸收水中的氧气