A:①②③
B:②③④
C:①③④
D:①②④
如图是机翼的模型,当飞机飞行时,迎面吹来的风被机翼分成两部分,机翼上方气流速度____ 下方气流速度,机翼上方的气压____ 下方的气压,因此在机翼的上下表面产生了____ ,飞机获得向上的____ .
根据句意及词首字母或汉语提示,补全单词。(1)Don't talk l____ in the classroom. It's impolite(不礼貌的).(2)The movie is so boring. I can't s____ it.(3)The clothes shop is on sale. This shirt is very c____ .(4)Yesterday, Kate studied for the English t____ .(5)Please ____ (记住)to turn off the lights.