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　　中国生物在各个国家开展的新冠疫苗Ⅲ期临床试验得到了当地政府的大力支持及充分肯定，多位政要鼎力支持，带头接种疫苗，并表示对中国生物新冠疫苗的安全性、有效性及Ⅲ期临床试验充满信心。

The fact that light travels at a finite, but very high, speedwas firstdiscovered in 1676 by the Danish astronomer Ole ChristensenRoemer. He observed that the times at which the moons ofJupiter appeared to pass behind Jupiter were not evenlyspaced, as one would expect if the moons went round Jupiterat a constant rate. As the earth and Jupiter orbit around thesun, the distance between them varies. Roemer noticed thateclipses of Jupiter’s moons appeared later the farther we werefrom Jupiter. He argued that this was because the light fromthe moons took longer to reach us when we were fartheraway. His measurements of the variations in the distance of theearth from Jupiter were,? however, not very accurate, and so his value for the speedof light was 140,000 miles per second, compared to themodern value of 186,000 miles per second. Nevertheless,Roemer’s achievement, in not only proving that light travels ata finite speed, but also in measuring that speed, wasremarkable - coming as it did eleven years before Newton’spublication of Principia Mathematica. A proper theory of thepropagation of light didn’t come until 1865, when the Britishphysicist James Clerk Maxwell succeeded in unifying the partialtheories that up to then had been used to describe the forcesof electricity and magnetism. Maxwell’s equations predicted thatthere could be wavelike disturbances in the combinedelectromagnetic field, and that these would travel at a fixedspeed, like ripples on a pond. If the wavelength of these waves(the distance between one wave crest and the next) is a meteror more, they are what we now call radio waves. Shorterwavelengths are known as microwaves (a few centimeters) orinfrared (more than a ten-thousandth of a centimeter). Visiblelight has a wavelength of between only forty and eightymillionths of a centimeter. Even shorter wavelengths are knownas ultraviolet, X rays, and gamma rays.

Be the conclusion what it may, the necessity of the trapper returning to the Texans was obvious. He told Rickard that he would try it at once, and no decision could be reached until after a talk with them.

　　《印度时报》报道，一名印军高官否认了有关媒体的说法。印军推特账号也抨击报道是“假新闻”，“毫无依据”。还有印度官员宣称，这一说法是“中国的心理战行动”。 

"Well, and what luck did you have?"

We had a great many visitors while waiting for the wrens: neighbors came to sit in our green shade, young housekeepers came looking for rooms to rent, and old birds who were leading around their noisy families came to dine with us. Once a pair of flickers started to light in the tree, but they gave a glance over the shoulder at me and fled. Later I found their secret—down inside an old charred stump up the canyon. Occasionally I got sight of gay liveries in the green sycamore tops. A Louisiana tanager in his coat of many colors stopped one day, and another time, when looking up for dull green vireos, my eye was startled by a flaming golden oriole. The color was a keen pleasure. Lazuli buntings, relatives of our eastern indigo-bird, sang so much within hearing that I felt sure they were nesting in the weeds outside the line of sycamores—I did find a pair building in the malvas beyond; a[28] pair of bush-tits, cousins of the chickadees, came with one of their big families; California towhees often appeared sitting quietly on the branches; linnets were always stopping to discuss something in their emphatic way; clamorous blue jays rushed in and set the small birds in a panic, but seeing me quickly took themselves off; and a pair of wary woodpeckers hunted over the sycamore trunks and worked so cautiously that they had finished excavating a nest only just out of my sight on the other side of the wren tree trunk before I seriously suspected them of domestic intentions.

“Do — do,” he murmured mechanically and absently, continuing to look at us. Then abruptly he broke out: “He’s going to marry her.”

"My eye, but there will be a crowd of people here! One reason I'm going up to David's is because I'm not allowed to stay up for the fun. Good-by. I'll take you up to see the boat some day next week," and beckoning the servant to follow with the aquarium, the young patrician disappeared through the outer door, and the Canovas made their way up a stately marble stair, and through a winding corridor until they came to a long narrow apartment whose walls were hung with canvases.

"Another friend of yours, Spennie?" inquired Sir Thomas politely, eying the red-haired speaker with interest.

1.“For,” he murmured, laying the palms of his hands together, “it is to be a long week-end.”

2.

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