Trees are useful to man in three important ways: they provide him with wood and other products, they give him shade, and they help to prevent drought(干旱) and floods. Unfortunately, in many parts of the world man has...Trees are useful to man in three important ways: they provide him with wood and other products, they give him shade, and they help to prevent drought(干旱) and floods. Unfortunately, in many parts of the world man has cut down a large number of trees every year.展开更多
It had been a pleasantly warm day, without much wind, and with enough cloud to prevent the heat of the sun becoming too great. Charles had spent a long time studying the___of the waterin the boat, and had discovered t...It had been a pleasantly warm day, without much wind, and with enough cloud to prevent the heat of the sun becoming too great. Charles had spent a long time studying the___of the waterin the boat, and had discovered that, by evening.it had____very slightly.展开更多
Australia was discovered at about 53,000 yearsago.Possibly the earlier settlers crossing intoAustralia came from Asia on a great land bridge at atime when the water level was lower.Once they were knowto people as“abo...Australia was discovered at about 53,000 yearsago.Possibly the earlier settlers crossing intoAustralia came from Asia on a great land bridge at atime when the water level was lower.Once they were knowto people as“aborigines”,that means“the first peopleof a country.”But today settlers come from countrylike Britain,Italy,Greece and Southeast Asian.展开更多
文摘Trees are useful to man in three important ways: they provide him with wood and other products, they give him shade, and they help to prevent drought(干旱) and floods. Unfortunately, in many parts of the world man has cut down a large number of trees every year.
文摘It had been a pleasantly warm day, without much wind, and with enough cloud to prevent the heat of the sun becoming too great. Charles had spent a long time studying the___of the waterin the boat, and had discovered that, by evening.it had____very slightly.
文摘Australia was discovered at about 53,000 yearsago.Possibly the earlier settlers crossing intoAustralia came from Asia on a great land bridge at atime when the water level was lower.Once they were knowto people as“aborigines”,that means“the first peopleof a country.”But today settlers come from countrylike Britain,Italy,Greece and Southeast Asian.
