问题描述：
This website is for members only . You can not read any articles ( )you are a member. A. because B. if C.unless D. though The park ( ) we visited yesterday is an excellent one . A.where B.in which C.whose D.that People found ( ) necessary to protect the environment long ago . A.this B.that C.it D.them 以上3道选择题请老师详细解答，谢谢老师！~
问题解答：
我来补答
解题思路： 掌握常考的句型
解题过程：
1. This website is for members only . You can not read any articles ( )you are a member.
A. because B. if C. unless D. though
同学您好，本题选C。本题考查的是条件状语从句。
句意：这个网站只为会员开放。你不能读任何的文章，除非你是一个会员。
引导条件状语从句的连词有if（如果）和unless（除非）。
If it is fine, we’ll go to the park. 如果天气好，我们就去公园。
unless在意义上等于if…not，但比if语气更强：
You will fail unless you study hard. = You will fail if you do not study hard.
除非你努力学习，否则你要失败。
2. The park ( ) we visited yesterday is an excellent one .
A.where B.in which C.whose D.that
同学您好，本题选D。本题考查的是定语从句的引导词。
句意：我们昨天参观的那个公园是很棒的一个。
在这个定语从句中，先行词是park，虽然是一个表示地点的名词，但后面的关系词不能用where，因为关系词在后面的定语从句中作动词visit的宾语，所以选that或which，因此正确答案为D。
判断关系代词与关系副词
用关系代词还是关系副词完全取决于从句中的谓语动词。及物动词后面无宾语，就必须要求用关系代词；而不及物动词则要求用关系副词。例如：
This is the mountain village where I stayed last year.
I’ll never forget the days when I worked together with you.
（错）This is the mountain village where I visited last year.
（对）This is the mountain village（which/that）I visited last year.
（错）I will never forget the days when I spent in the countryside.
（对）I'll never forget the days（which/that）I spent in the countryside.
习惯上总把表示地点或时间的名词与关系副词 where，when联系在一起。此两题错在关系词的误用上。
3. People found ( ) necessary to protect the environment long ago .
A.this B.that C.it D.them
同学您好，本题选C。本题考查的是it在句子中作形式宾语。
句意：很久以前人们就发现保护环境是很必要的。
it作形式宾语的常用句型为：主语+think / consider / find + it + adj. + to do sth.
如：I find it necessary to talk to Tom once again. 我觉得再和汤姆谈一次很有必要。
再看一道题：
All of us found _____ difficult to work out the math problem.
A.it B.that C.which D.what
本题选A。我们都发现计算出这道数学题很难
最终答案：略
