请问大全1－11和21

carolyue

11.   Although the lesser cornstalk borer is widely distributed, control of them is necessary only in the South.

(A) the lesser cornstalk borer is widely distributed, control of them is

(B) widely distributed, measures to control the lesser cornstalk borer are

(C) widely distributed, lesser cornstalk borer control is

(D) the lesser cornstalk borer is widely distributed, measures to control it are（D）

(E) it is widely distributed, control of the lesser cornstalk borer is

请问A中除了them是复数错了之外还有什么地方错呢？

21.   While the owner of a condominium apartment has free and clear title to the dwelling, owners of cooperative apartments have shares in a corporation that owns a building and leases apartments to them.

(A) While the owner of a condominium apartment has free and clear title to the dwelling,

(B) The owner of a condominium apartment has free and clear title to the dwelling, but

(C) Whereas owners of condominium apartments have free and clear title to their dwellings,

(D) An owner of a condominium apartment has free and clear title to the dwelling, whereas（C）

(E) Condominium apartment owners have a title to their dwelling that is free and clear, while

请问A中的while有什么不对啊？while和whereas有什么区别啊？谢谢，这个问题以前有人问过，但我还是不明白

hougang

while, whereas, or although
The use of "while" to show contrast is common and accepted in informal usage. In
formal writing, however, "while" should be reserved to show that two or more
events occur at the same time. In the following sentence, the two events are
occurring simultaneously.

Measurements were taken while the specimen was rotating in the rig.
For comparisons and contrasts, "whereas" and "although" should be used instead
of "while."

Positions are logged manually, whereas temperatures and pressures are recorded
automatically by the thin-film sensors.
These two events happen in different ways. They do not necessarily occur at the
same time.

Although positions are logged manually, temperatures and pressures are recorded
automatically by the thin-film sensors.
The meaning of this sentence is similar to the previous one, but it places more
emphasis on the differences between the two events.

Indiscriminate use of "while" where "whereas" or "although" would be more
appropriate can even result in ambiguity and misunderstanding:

While my cat, Princess, eats quickly, she enjoys a leisurely stroll.
Does she do both at the same time? Using "whereas" or "although" in this sentence
would clear up the confusion.



In each sentence, select the best choice for formal writing:

While /Although the method is efficient for most applications,
it can produce errors when small, irregularly shaped specimens are tested.
Place the sample into the rig while / whereas the power is off.
The Structures Division had responsibility for the fan blade design, while /whereas
the Materials Division was to develop the composite material for the blade. (The two
projects are not necessarily happening at the same time.)
While /Although the experiment was thermal cycling, an inert atmosphere was
maintained to avoid oxidation of the aluminum framework.
The single-crystal material is somewhat stronger, while /whereas the composite is
significantly lighter.
Make sure that excessive pressure is not applied while / whereas the surfaces are in
contact with each other.

carolyue

哇，好长啊，是你自己总结的吗？我看明白了，谢谢你！

还有11题，哪位大侠给我指点指点啊？