英语
- Scientists tell us that what we see in the universe is only a small part of what is there.The rest is invisible, include dart matter and dart energy. These two unknowns make up around 95% of the uninverse. Evidence of their existence comes from their effects on what we can observe,such as the motion and positions of distant galaxies.
- To envolve means to change or improve over a period of time.
Life forms envolve because they have to adapt in order to survive. - A child from a very rich family may inherit a lot of money.(inherit a large fortune)
- 1.A cycle is a series of events that repeat, such as the daily cycle of light and dart.
2.The number of times a cycle repeats itself within a period of time is its frequency.
3.The time it takes for a cycle to repeat itself is its period. - According to science we have all evolved from one-celled organisms.
- There are many kinds of forces. There are forces of attraction, such as the force between positive and negative electric charges. There are also forces of repulsion.For example, two objects with the same electric charge will repel each other.
- In marriage, a wife's attempt to transform the behavior of her husband is often unsuccessful.
- Knowing when and how to praise someone is an important skill.
- Some people appreciate constructive criticism, which can help them develop their skills.
- Some people are discouraged if they don't receive praise or recognition(识别，承认，赞誉) for their work.
- The challenge for humans will be our ability to adapt to our changing environment.
- conserve
- It takes the advantage of the fact that the earth is like a huge bar magnet.
- seasonal variations, for example, can be one of the greatest challenges for animals to overcome.
- This energy comes from the air currents generated by the wings.
- Some birds migrate thousands of kilometers each year to deal with seasonal changes.
- And even the way birds fly together is amazing.
- Many die along the way, but enough of survive to breed and preduce the next generation.
- a landmark is something easy to see or remember,like a river or bay.
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Humans also migrate, but seldom if ever for seasonal variations.
图片发自简书App
图片发自简书App
