涛涛2-Q33,34

eric123

涛涛2-Q33:

When an active tooth in the shark’s jaws is lost or worn down, many spare teeth lie in seemingly limitless reserve, each of which are ready to slide into the appropriate position.

 

1. When an active tooth in the shark’s jaws is lost or worn down, many spare teeth lie in seemingly limitless reserve, each of which are ready to slide into the appropriate position.
2. Whenever an active tooth is lost or worn down, many spare teeth lie in seemingly limitless reserve in the shark’s jaws, which are each ready to slide into the appropriate position.
3. Many spare teeth lie in seemingly limitless reserve in the shark’s jaws, each one of which are ready to slide into the appropriate position when an active tooth is lost or worn down.
4. The many spare teeth lying in seemingly limitless reserve in the shark’s jaws, each one of which is ready to slide into the appropriate position whenever an active tooth is lost or worn down.
5. In the shark’s jaws, many spare teeth lie in seemingly limitless reserve, each one ready to slide into the appropriate position whenever an active tooth is lost or worn down.

为什么选A?each of which 应用is ? 

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Q34:

NASA’s methodical approach to the exploration of Mars has not yet answered the questions of whether biological life forms ever emerged on Mars and whether, presuming such life forms having left fossil traces to begin with, those traces can still exist in some moist recesses of the cold and arid planet.

 

1. and whether, presuming such life forms having left fossil traces to begin with, those traces can
2. and whether, if it is presumed that such life forms left some fossil traces to begin with, can those traces
3. and whether, presuming such life forms left fossil traces to begin with, those traces
4. and, presuming such life forms did leave some fossil traces to begin with, if they can
5. and, presuming such life forms to have left fossil traces to begin with, if they

为什么选A?A中为什么用having left ?

dlmmdajgal

同问，33，这叫虚拟？应该都用复述。但C为什么错？

34 和你一样，我选了C,不过是不是 ever ... can有讲究？少了can更严重，所以小错having就没事？