1.) I would appreciate it______you call back this afternoon for the doctor's appointmentA.until B.if C.when D.that2.)____the poem a second time the meeaning will become clearer to youA.Your having read B.while reading C.If reading D.when you readkey & reason第二题选D，但是我还是不是很明白原因~

1 B 如果你能为医生的见面回电我会很感激地
2 A 主句的主语是the meaning ，从句就要加上主语，a second time 用完成式

第一题应选B
I (`ll/would) appreciate it if...是一个固定句型 意思是如果...我就太感激了。是一种委婉的请求方式
第二题应该选D
从句和主句的主语不一样时,(与是否是人无关)不能省略!!!!!!!
When you read the poem a second time,the meaning will become clearer to you. (从句和主句的主语不一样)
When/if/after reading the poem a second time,you will never forget it. (从句和主句的主语一样)
Before/When getting a new job in this company last March, I had worked as a engineer for 10 years. (从句和主句的主语一样)
Before/When this company offered me a new job for me last March, I had worked as a engineer for 10 years.(从句和主句的主语不一样)

第一道题目选择B
按照意思就能选择出来了.“如果”
第二题选择D
这个句子后半部分“the meeaning will become clearer to you”是一个完成的句子.
在英文语法中,一个句号中只能有一个完整的句子,除非有连词链接.
很明显“the meeaning will become clearer to you”前面并没有连词.那么“____the poem a second time”这部分必然是个从句.
再看“the meeaning will become clearer to you”的主语是“the meeaning ”.那如果从句省略主语,则应该与主句的主语保持一致,也应该是“the meeaning”.
很显然B和C省略了主语,但是read是人发出的,而不是“the meeaning ”.首先淘汰掉.
其次A选项用了一个现在完成时（这里用了省略系动词的形式,但是还是现在完成时）,明显主语是将来时,两者时态不能兼用.
最后只剩下了D.
读一下句子,意思语法完整,时态正确.OK就选择D了.

1)选B
第一部分：I would appreciate it
第二部分：if you call back this afternoon for the doctor's appointment
第二部分不是第一部分的宾语或者定语（否则的话，有可能用that连接），两部分是并列的，也可以简单理解为一个 If ... , I will/ would ...“如果⋯⋯，我就⋯⋯”的条件结构
2）选C
因为if reading实际上是if you are reading的省略