介绍:
Day99.
It has been found that certain bats emit squeaks and by receiving the echoes, they can locate and steer clear of obstacles------or locate flying insects on which they feed. This echo-location in bats is often compared with radar, the principle of which is similar.
人们已经发现，某些蝙蝠发出尖叫声并靠接受回响来锁定和避免障碍物——或者找昆虫吃。蝙蝠这种回响定位法常拿来和原理与之很相近似的雷达相比。
Emit [ɪˈmɪt] vt.发出;发射;颁布;发表
A fixed star can emit light and heat by itself.
恒星本身发光发热。
Polly blinked and emitted a long, low whistle.
波莉眨了眨眼，吹了一声低沉而悠长的口哨。
It is unlawful for factories to emit black smoke into the air.
现在，工厂往空气中排黑烟是违法的。
squeak [skwik]
n.短促的尖叫声，，吱吱的叫声;尖厉刺耳的噪音;机会
vi.短促地尖叫，吱吱叫;发出尖厉刺耳的噪音;告密
vt.以尖厉的声音说话;使发出吱吱声
Mice squeak.
老鼠吱吱叫。
My father had a narrow squeak in the automobile accident.
我父亲在这次车祸中死里逃生。
We managed to squeak through the match.
我们终于设法险胜了这场比赛。
Echo [ˈekoʊ]
n.回声，共鸣;（言语、作风、思想等的）重复;重复者;[无线电]回波
vt.重复，效仿;随声附和;类似;发射（声音等）
vi.被重复;产生回响;充满回声
His feet echoed on the bare board floor
他的脚步声在没铺地毯的木地板上发出回响。
I hear an echo of the thinking that got us into this mess in the first place
我听到有人重提那个最先使我们陷入这一困境的想法。
Steer [stɪr]
vt.& vi.引导;驾驶;操纵，控制
vt.掌（舵）
vi.行进
n.阉公牛，肉用公牛;〈美俚〉建议;关于行路（或驾驶）的指示
What is it like to steer a ship this size?
驾驶这么大的船感觉怎么样？
Nick steered them into the nearest seats.
尼克将他们领到最近的座位上。
The new government is seen as one that will steer the country in the right direction
新政府被认为能将国家引向正确的方向。
