BC中的They 是冗余的，因为原文已经说了most tenants. 排BC
Conversion（ 转换这件事）比较 being converted （转换的状态）更优
whether（可做表语从句，宾语从句连词） if（条件） 两者择一，whether更优

whether 和 if
两者选一，用whether
if表示如果，连词引导的从句

Also, we don't want to say "undergoing being converted." Like most uses of "being," this is awkward and unnecessary. In this case, we have a simple noun--"conversion"--so there's no reason not to use that.

undergo being冗长
be动词后面表是否时只能用whether，不能用if

本题，“The first decision for most tenants is whether to sign a pledge”. 已经有“for most tenants ”表明sign动作的主语，不需要再加they。
“ It remains to be seen whether or not this idea can be put into practice. ”这个句子则whether带了自己的主语。

1、undergo，动词，经历
tenants living in a building undergoing conversion to cooperative ownership，undergoing动词分词作定语修饰building，正在经历转成公司产权的建筑。

2、for/of sb to do sth为不定式的复合结构，一般情况下，不定式这一动作的执行者就是句子的主语。但是，有时不定式的动作执行者不是句子的主语，此时不定式的前面要加一个名词或代词来充当不定式的逻辑主语。如：
It's impossible for a child to learn everything.
She waved the red flag for the car to stop.

they冗余。undergo（v）being converted （o）

那A is if to sign 是否也是表语从句？

being表达ad含义，和undergo本身的意思也重复了吧

关于“being”有一点不是很赞同老师的解释。
转换为共同所有权应该是修饰”building“的吧，那就不存在老师说的反复出现啥的。这个解释是不是就不通了。更赞同下面的这个解释

Also, we don't want to say "undergoing being converted." Like most uses of "being," this is awkward and unnecessary. In this case, we have a simple noun--"conversion"--so there's no reason not to use that.
_________________

Dmitry Farber | Manhattan GMAT Instructor | New York

"whether or not" is considered redundant on the GMAT.

Also, we don't want to say "undergoing being converted." Like most uses of "being," this is awkward and unnecessary. In this case, we have a simple noun--"conversion"--so there's no reason not to use that.

if 意为如果，一般引导条件状语从句，whether意为是否，可用于二选一，可以引导表语从句

pledge保证 抵押
BC：whether 后they should多余

A：动名词短语being converted to cooperative ownership应改为名词短语的conversion to cooperative ownership。
反复出现的事情，必然是有时间终止点的事情，必须用名词短语。表达这件事，而不是状态

如果理解成a building转换成公有所有制，不是就只发生一次转变嘛？

引导表语从句：只能用whether，不能用if
Personalized?No Process-oriented? No--用名词 而非动名词

Also, we don't want to say "undergoing being converted." Like most uses of "being," this is awkward and unnecessary. In this case, we have a simple noun--"conversion"--so there's no reason not to use that.
_________________

Dmitry Farber | Manhattan GMAT Instructor | New York

再刷这个题，感觉这个“ a building undergoing being converted to cooperative ownership ”跟“a building undergoing conversion to cooperative ownership”意思是不是不太一样呢？
前者是a building undergoing （it）being converted to cooperative ownership，意思是这个楼被转换成合伙制。
后者“ to cooperative ownership”应该做宾补修饰conversion，这个转换是变为合伙制
不知道能不能这么想呢？。。

SVC结构，主语decision主观性强，主补用不定式

毕老师，我有个问题： whether or not 在GMAT中算不算wordy?

if 在书面语中只能表示如果，不能表示是否。直接AD排除。