蝉发音的秘密

蝉为么会发音，对我来说一直是个谜。为了揭开这个秘密，我常常躲在树下悄悄地观察。我发现蝉鸣时，总是“挺胸”、“翘尾”。

why cicadas can pronounce has always been a mystery to me. in order to uncover the secret, i often hide under the tree and observe it quietly. i found that cicadas always "hold their chests up" and "raise their tails" when they chirp.

这是为什么呢？一天，我捉到了一只蝉，进行了观察研究。我摘掉了蝉的翅膀，把它放在地上，它在地上扑打着小翅膀，叫着；我又折断了它针状式的嘴，可它仍然叫着。蝉究竟靠什么发音呢？经过反复观察，我发现这声音好像是从胸部发出来的。于是，我把它捉起来看，发现它凹部的两侧，各有一片鱼鳞似的硬壳，像钳甲一样，里面有一对透明薄膜。蝉呜时，簿膜地回动，我用手轻轻地一扞这个地方，蝉就叫了。我不停地捏，它就不停地叫。我想：这对簿膜就是它发音器吧！我把簿膜刺破，再怎么捏，它也不叫了。后来妈妈告诉我这是蝉的“响板”，是雄蝉特殊发音器。发音膜的肌肉收缩振动，蝉就会发出声音。雌蝉没有“响板”，所以是哑巴。

why is that？ one day, i caught a cicada and made an observation. i took off the wings of the cicada and put it on the ground. it flapped its little wings on the ground and cried. i broke its needle like mouth again, but it still cried. what pronunciation does cicada depend on？ after repeated observation, i found that the sound seemed to come from the chest. so i caught it up and saw that on both sides of its concave, there was a hard shell like a fish scale, like a pair of tongjia, with a pair of transparent films inside. when the cicada whines, it moves in a thin film. i use my hand to gently shake this place, and the cicada calls. i kept pinching, and it kept barking. i think: this pair of film is its pronunciation device! i pricked the film. no matter how i pinched it, it wouldn't scream. later, my mother told me that this is the "soundboard" of cicadas, a male cicada special pronunciation device. the muscles of the vocal membrane contract and vibrate, and cicadas make sounds. female cicadas are mute because they don't have a soundboard.

这时，我才明白，蝉叫的时候，为什么总爱“挺胸”和“翘尾”了。揭开了蝉发音的秘密，我又一次尝到了动脑筋、学科学的甜头。

at this time, i can understand why cicadas always love "open chest" and "cocked tail". the secret of cicada's pronunciation has been revealed, and i have once again tasted the sweetness of using my brain and learning science.