To get a full appreciation of what this means we must turn first to some recent human inventions.
要透彻理解这句话的意义，我们应先回顾一下人类最近的几项发明。
新概念英语第四册 Lesson 7 Bats

📚 句中词汇解析

从本句中提取的重要词汇

appreciation [ə,priʃɪ'eʃən] 词频3 词根: preci
n. 欣赏；鉴赏;感谢;评估;增值;
💡 ap一再+preci价值+ation名词后缀，表示行为 → 一再估价 → 评价，鉴赏，欣赏
"an aesthetic appreciation of the landscape"
用审美的眼光欣赏风景
近义：recognition, regard, acceptance, thankfulness, acknowledgement, acknowledgment 反义：thanklessness, ungratefulness, disloyalty, reduction, devaluation
recent ['risnt] 词频1
adj. 最近的;新近的;近代的;[地]全新世的;
💡 recent- “新的,新鲜的”
"Recent research has cast new light on the causes of the disease."
最新研究使人们进一步了解了这种疾病的起因.
近义：latest, modern, new, novel, unworn, young 反义：antiquated, antique, indigenous, archaic, longstanding, native
human ['hjumən] 词频1 词根: hum
n. 人，人类; adj. 人的;有人性的;显示人类特有弱点的;人本性的;
💡 hum土,地+an名词后缀，属于...的，传说人是由土造出的 → 人类
"The teacher drew an analogy between the human heart and a pump."
老师打了个比喻，把人的心脏比作水泵。
近义：mortal
full [fʊl] 词频1
adj. 满的，装满的;完全的，完整的;丰富的;详尽的; adv. 极其，十分;充分地，完全地;整整;直接地; n. 充分，完全;全部;完整;极盛时; v. 把衣服缝得宽大;把裙子缝出皱褶;[印]蒸洗，漂洗;
💡 因为fill（充满）所以full(满的）
"The streets were noisy and full of activity."
街上熙熙攘攘，车水马龙。
近义：felt, abounding, laden, overcrowded, overstuffed, plump 反义：hollow, unladen, unoccupied, vacant, void
means [minz] 词频2 词根: 心智
n. 方法（ mean的名词复数）;手段;收入;财富; v. 意味着（ mean的第三人称单数）;引起;打算或注定要某人成为或做某事;
"The inquiry is by no means cut and dried."
调查之事远未盖棺定论。
近义：approach, manner, method, mode, process, strategy

📚 更多「新概念英语第四册」例句

It has been found that certain bats emit squeaks and by receiving the echoes,
人们发现，某些蝙蝠能发出尖叫声，
For this reason there is no risk to the customer in the practice,
因此，这种做法对储户毫无风险。
The currents of air that the walls of the ship direct upwards, as well as in the line of its course, are enough to give the great bird with its immense wings sufficient sustenance and progress.
沿船体的上升的气流和沿航线向前的气流给这种巨翼大鸟以足够的浮力和推力。
The majority of thepatients attending the medical out-patients departments of our hospitals
在医院门诊部看病的大多数人
when a significant number of people are living permanently in space.
如果有相当数量的人永久性地住在太空，
to overcome all but the most instantly fatal illnesses and accidents.
了暴病而死或意外事故外，至少足以克服一切一般疾病和事故。