Today, enough soundings are available to enable a relief map of the Atlantic to be drawn and we know something of the great variety of the sea bed's topography.

be available to do ^{（事物做主语）有某个东西可供…}

• Funds are available to assist teachers who want to attend the conference. ^{有资金可供帮助想参加会议的教师。}
• The arts should be available to more people at prices they can afford. ^{艺术品应该以人们支付得起的价格提供给更多人。}
  
• Rental Information Lockers are available to store any belongings during your visit. ^{租赁柜可以在您参观期间存放你个人物品。}

know … about / of … ^{对…有所了解}

• I don’t know anything about this. ^{我对此一无所知。}
• Not much is known about his background. ^{关于他的背景知之甚少。}
• You know nothing of this business. ^{你对这生意一无所知。}

Since the sea covers the greater part of the earth's surface, it is quite reasonable to regard the sea floor as the basic form of the crust of the earth, with, superimposed upon it, the continents, together with the islands and other features of the oceans.

it is (quite) reasonable to do ^{做…是完全合理的}

• It is quite reasonable for China to demand Japan to thoroughly rethink the Yasukuni Shrine issue.
• But it seems reasonable to think sunscreen gives people a false sense of security in the sun. ^{但是认为防晒霜会让人们在阳光下产生一种虚假安全感的这种想法似乎是合理的。}
• It seems reasonable to expect rapid urban growth. ^{看起来期待城市会飞速发展是有道理的。}
• It is reasonable to assume (that) the economy will continue to improve. ^{认为经济将继续好转是有道理的。}
• It is reasonable to assume that he knew beforehand that this would happen. ^{有理由认为他事先就知道会发生这样的事。}

superimpose A on / upon B ^{把A附加到B上}

• She superimposed a grid on the map to analyze data. ^{她在地图上附加了一个网格来分析数据。}
• Text was superimposed on the image for clarity. ^{文字被附加在图像上以提高清晰度。}

独立主格:  (with) + n. + 非谓语  ^{在句中常作状语或定语}

… with the continents, to ether with the is ands and other features of the oceans superimposed upon it. ^{正常的逻辑主语在前面会导致头重脚轻}

• It is possible that upon such an occasion a battle ensued, with the sharks being driven away or killed. ^{做结果状语}
• The silence was suddenly broken when a large car, with its headlights (being) on and its horn blaring, roared down the arcade. ^{做伴随状语}
• One man stayed at the wheel while two others with black stockings (being) over their faces jumped out and smashed the window of the shop with iron bars. ^后置定语
• …, and at this point, according to my father, I should be looking at farms and cottages in a valley, with the spire of the church of our village showing in the far distance. ^{后置定语，修饰valley}
• Apart from an interesting-looking carved dagger, the box was full of crockery, with much of it broken. ^后置定语
• In the nineteenth century, a novelist would bring his story to a conclusion by presenting his readers with a series of coincidences —with most of them wildly (being) improbable. ^后置定语
• The village seemed deserted, with the only sign of life being an ugly-looking black goat tied to a tree on a short length of rope in a field nearby. ^{定语或状语}
• Collecting, by occupying spare time so constructively, makes a person contented, with no time  (being) for boredom. ^状语

独立主格和非谓语动词一样，一般是为了突出句中的次要信息。

The continents form rugged tablelands which stand nearly three miles above the floor of the open ocean.

stand ^{矗立/高达...(系动词)}

• Strange forms stand in gardens, and outside buildings and shops.
• The Monument to the Heroes stands in the center of The Square.
•  She stood three feet high and her hands rested on her hips. ^有多高
• An American team explored a temple which stands in an ancient city on the promontory of Ayia Irini. ^位于...
• The tower stands 20 meters high. ^{这座塔高达20米。}
• The Monument to the Heroes stands in the center of The Square. ^{英雄纪念碑矗立在广场中心。}

From the shore line, out to a distance which may be anywhere from a few miles to a few hundred miles, runs the gentle slope of the continental shelf, geologically part of the continents.

run ^{v.（使）延伸;持续，延续}

• There was a path running through the middle of the forest.

全部倒装（把全部谓语置于主语之前）

• Out went he. X ^{主语不能是代词(Out he went.)}
• On the hill saw John Mary. X ^{谓语是及物动词(On the hill John saw Mary.)}

geologically ^{从地质学角度}

• The continental shelf is geologically part of the continents. ^{大陆架从地质学角度是大陆的一部分。}
• Geologically, the area is highly unstable. ^{从地质学角度看，该地区极不稳定。}
• The rock formations were studied geologically. ^{这些岩层被从地质学角度研究。}

The real dividing line between continents and oceans occurs at the foot of a steeper slope.

occur ^{存在于/发生}

• Minerals occur in the earth’s crust. ^{矿物质存在于地壳中。}
• Earthquakes often occur in this region. ^{地震常发生在此地区。}