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huynhthituanloc
2 năm trước
bài 2 tìm x a, x/3 = 12/9 b, 5/x = -15/21 c, 3/7 = x/21 d , -5/4 = 15/x diễn giải ra nếu ko diễn giải = bc
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Reading passage and choose the correct answer. There are desert plants which survive the dry season in the form of inactive seeds. There are also desert insects which survive as inactive larvae or pupae. In addition, difficult as it is to believe, there are desert fish which can survive through years of drought in the form of inactive eggs. These are shrimps that live in the Mojave Desert, an intensely dry region in the southwest of the United States where shade temperatures of over 500C are often recorded. The eggs are in the size and have the appearance of grains of sand. When sufficient spring rain falls to form a lake, once every two or five years, these eggs hatch. Then the water soon swarms with millions of tiny shrimps about a millimeter long which feed on microscope plant and animal organisms which grow in the temporary desert lake. Within a week, the shrimps grow from their original 1 millimeter to a length of about 11/2 centimeters. Through the time that the shrimps are rapidly maturing, the water in the lake equally rapidly evaporates. Therefore, it is a race against time. By twelfth day, when they are about 3 centimeters long, hundreds of tiny eggs form on the underbodies of the females. Usually, bu this time, all that remains of the final hours of their brief lives, the females lay their eggs in the mud. Then, having ensured that their species will survive, the shrimps die as the last of the water evaporates. If sufficient rain falls the following year to form another lake, the eggs hatch, and once again cycle of growth, adulthood, egg-laying, and death is rapidly passed through. If there is insufficient rain to form a lake, the eggs lie dormant for a year, or even longer if necessary. Occasionally, perhaps twice in a hundred years, sufficient rain falls to form a deep lake that lasts a month or more. In this case, the species passes through two cycles of growth, egg-laying and death. Thus the species multiplies considerably, which further ensures its survival. 1. What does the passage mainly discuss? A.The effects of drought in the desert. B.The lifespan of fish eggs in the desert condition. C.The survival of the insects in a desert climate. D.The importance of deep lakes in the desert. 2. The word “form” in the first paragraph is the closest meaning to A.style B.shape C.nature D.design 3. From the passage, it can be inferred that the Mojave Desert is unusual because A. it is hot even in the shade B.rain rarely falls there C.it shelters inactive life D.very little survies there 4. The author compare inactive eggs to . A.shrimps B.sand C.larvae D.seeds 5. The word “These” in the first paragraph refers to . A.plannts B.eggs C.insects D.fish 6. According to the passage, the eggs originate . A.in the sand B.on the female C.in the mud D.in the lake 7. The word “swarms” in the second paragraph could best be replaced by . A.abounds B.grows C.crowd D.supports 8. According to the passage, approximately how long does a shrimp live? A.1 week B.12 days C.13 days D.14 days plus 9. The word “dormant” in the last paragraph is closest meaning to . A.dead B.asleep C.passive D.empty 10. What does the author mean by the phrase “a race against time” in the second paragraph? A.The shrimps are intense competition to reproduce. B.The shrimps must reproduce before the water recede. C.The shrimps do not have enough time to reproduce. D.Death occurs before the shrimps can reproduce.

1. The children are interested in computer games. (usually) ……………………………………………………………………………………… 2. My mother is busy on Sundays. (always) ……………………………………………………………………………………… 3. His brother gives him a present. (sometimes) ……………………………………………………………………………………… 4. We don’t go fishing in the winter. (often) ……………………………………………………………………………………… 5. What does she do at recess? (usually) ……………………………………………………………………………………… 6. I help my mother with the housework. (often) ……………………………………………………………………………………… 7. They watch T.V. (never) ……………………………………………………………………………………… 8. Hoa and Mai play tenis in the garden. (often) ……………………………………………………………………………………… 9. What does she do in the afternoon? (usually) ……………………………………………………………………………………… 10. She does the housework after school. (often) ………………………………………………………………………………………

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