2016年二十国集团领导人杭州峰会(G20)上,身着蓝绿色调服装的“小青荷”志愿者,从峰会会场到宾馆酒店的迎宾台,从西湖边的微笑亭到机场车站,向世界展示着灿烂的笑容和温馨的服务。“小青荷”志愿者们( )
①积极参与社会公益活动,服务社会 ②促进了我国精神文明建设
③浪费了自己的时间,没有得到回报 ④是亲社会行为,体现了强烈的社会责任感和服务意识
A: ①②③
B:②③④
C:①③④
D:①②④
让杂合高茎豌豆自交,后代中出现高茎和矮茎两种豌豆,且两者的比例大约为3∶1,这种现象在遗传学上称为( )
Welcome to Wenzhou Zoo! There are many different kinds of animals in the zoo.They come from different countries and they eat different food.
Beibei is a cute panda.She is five years old from China. She is black and white.She likes eating bamboo and drinking water.
Martin is a big elephant.He is ten years old with a long nose.He likes eating grass. People can teach* him to do much work to help them.
Dudu is a monkey. He is two years old from Japan.He likes eating bananas and cakes.He often lives in the trees.
Nick is a lion. He is strong.He is nine years old from England.He likes eating meat. He is very happy in the zoo.
有专家说:“就像1914年时那样,一起小事件就能够触发同盟义务,引发一场覆盖面更广的战争。”这起“小事件”是( )