共生原理
参考答案:是生物与生物之间、不同系统之间的合作共存、互惠互利关系。人类与自然界的共生是指人类社会与自然界之间的互利共存关系。
续写句子。请用“如果……那么……”再写两个句子。
当我们毕业后离开了父母,才真正懂得珍惜,希望能与父母在一起,哪怕是一次谈话,一顿饭。可是,生命不相信如果……不懂得珍惜的结果就是失去。如果我那时给父母提一桶水,替他们洗洗衣服,那么今天我就不会后悔;如果___________________________那么____________________________;如果__________________________那么_____________________________。
Ink-jet printer belongs to nonimpact printers in which the characters are formed by projecting particles or droplets of ink on to paper. (71) printer is also a n0nimpact printer in which the characters are produced by applying hot elements to heat-sensitive paper directly or by melting ink from a (72) on to plain paper. Electrostatic printer creates an electrostatic latent image, which is then made visible by a toner and transferred and fixed on paper. An electrostatic printer may be used in some instances as a (73) . Laser printer creates, by means of a laser beam directed on a (74) surface, a latent image which is then made visible by a toner and transferred and fixed on paper. Magnetographic printer creates, by means of magnetic heads operating on a metallic drum, a latent image which is then made visible by a toner and transferred and fixed on paper. Computer-output-microfilm (COM) printer produces on a photographic film a (75) of each page.
(74)是()
A.brightness
B.photosensitive
C.emitter
D.light-sensitive