TOEIC longman advance裡的問題 - 自學

有些題目不太懂
請大家幫我解答
謝謝

P.117 Q.8
The boss will offer him a promotion if he _(A)_
to be more tactful.

A)will learn B)had learned C)should learn D)were learning
我選D
P.120 Q.8
The survey indicates profits are up; business _(D)_.

A)is being good B)were good C)good D)has been good
我選A=>不是正在好轉嗎?
P.126 Q.6
His efforts,which he claims are his best, would be
-----(A)----
less than satisfactory even to the least demanding
-------(B)------------ -------(C)---------
person than myself.
---(D)------
Ans:(C)
請問錯在哪裡呢
P.138 Q.9
The CEO deciding to resign, thereby is accepting all
---------(A)-------------- ------(B)-----------
responsibility for the scandals jeopardizing the company,
-----------(C)-------------------
has proven to be good for the value of the stock.
---(D)----
Ans:(B)
請問錯在哪裡呢

閱讀文章部份無法整個打出來 請有文本的人解答我的疑惑~
P.151 Q.10 從哪裡看出來也有提供health insurance
P.156 Q.7 為什麼不會是a member of a citizens group
P.164 Q.2 為什麼不是B 退換和退款
P.165 Q.4 我選D耶...purchases calculators
P.172 Q.11 為何是A而不是B
Q.13 為何是B clerks不能停車而不是A visitors

好多喔~拜託好心人解除我的疑惑
感激不盡
--------------------是我程度爛嗎 怎麼這麼多問題>"<

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