指甲是生長在手指頭尖端的細(xì)薄角質(zhì)物.Nails are thin horny growths at the ends of the fingers.這架飛機有一套尖端的電子導(dǎo)航系統(tǒng).The airplane has a sophisticated electronic guidance system.刺:葉特化成為具有鋒利尖端的結(jié)構(gòu).Spine A modified leaf reduced to a sharply pointed s...