McGraw-Hill's GMAT,2011作为备考怎么样？

calovedebbie

                                   WORKING DATA SUFFICIENCY PROBLEMS EFFICIENTLY
The key to working Data Sufficiency problems efficiently is to master the decision tree— remember, AD or BCE— and to work problems only as far as is necessary to determine their sufficiency. In some situations, such as those involving algebraic linear equations, you can tell that the problem is solvable even if it would take a long time to solve. We’ll discuss these types of equations in the algebra material in Chapter 4.
There are a few useful things to know about how the test writers compose Data Sufficiency questions. For example, when a Data Sufficiency question starts with is, are, or does, you are trying to find a yes or no answer, rather than a number. A statement is sufficient as long as it gets you a definite yes or no; either one means you have enough information to answer the question. If you can get both a yes and a no depending on which numbers you use, that statement is not sufficient.
This is important to note because it is easy to confuse a yes answer with the statement being sufficient to answer the question. These questions may seem more complicated than other Data Sufficiency questions, so be sure to take your time and keep track of your work on your scratch paper.
With practice, you will become used to this format and it will no longer seem confusing.
Also, when the answer to a question is D—“EACH statement ALONE is sufficient”—the answer provided by both statements will be the same; you should not see a situation in which one statement leads to a yes and the other statement to a no, or where one statement leads to a 6 and the other to a 7. There is no reason why ACT could not create a question in this way— the directions and the answer description for D would not disallow it— but past questions have generally followed this pattern of consistent answers.
McGraw-Hill's GMAT, 2011 Edition (5th Edition)  这本书怎么样？

calovedebbie

看来没什么用...不传了 UNC图书馆里看到的...以为挺新 能有点帮助..