that-those, there-it, this-which
1. that-those：一個帶有比較意思的句子，若比單數則用that當代名詞，若比複數則用those。
例：
1. The stories in this book are not so interesting as those in that book.
2. The climate in Singapore is milder than that in India.
2. It-there：It可用於下列幾種句型：
(a) 當虛主詞，代替後面的不定詞片語或that所引導的名詞子句，其結構為
to+原形動詞
“It+be+Adj或NP+ for+O+to+原形動詞”
That+S+VP
例：
1. It is difficult to reach an agreement.
2. It is difficult for them to reach an agreement.
3. It is a truth that practice makes perfect. (熟能生巧是事實)
問題思考：
下列空格應使用什麼結構?
1. It+be+Adj或NP+ .
2. +to+原形動詞
that+S+VP
(b) 當虛受詞，代替後面的不定詞片語或that所引導的名詞子句，其結構為
to+原形動詞
“S+V+it+Adj或NP+for+O+to+原形動詞”
that+S+VP
此種句型中，動詞表達“視為”或“使‥”，如think, consider, believe, find, take, make等。
例：
1. He makes it a rule to get up at 5：30.
2. We consider it impossible for them to finish the work in two days.
3. People believe it true that practice makes perfect.
問題思考：
下列空格應該用什麼結構?
1. S+V+it+Adj或+NP+ .
2. S+ +to+原形動詞
that+S+VP
(c) 當加強語氣，加強副詞，其結構為“It+be+adv+that+S+V”，這種結構的考詴重點在於不管是時間副詞或地方副詞，連接詞一律要用that。
例：
1. It was in 1981 that I first met him. (加強時間副詞)
2. It was in New York that he became famous. (加強地方副詞)
3. It was because he was sick that he didn’t go to school. (加強because所引導的副詞子句)
(d) 當加強語氣，加強名詞，其結構為
who
“It+be+NP+which 所引導的形容詞子句”
whom
that
例：
1. It was John who(that) won the the race. (加強John)
2. It was Mary whom(that) Robert was in love with. (加強Mary)
(e) There：There最常考之結構為“There+be+NP”，語意上表達“有”，be動詞的單複數由NP決定。
例：1. There is a book on the desk.
2. There are many different kinds of insects in the forest.
請注意，“It或They+be+NP”表達“是”。
例：
1. It is a beautiful day.
2. They are good students.
3. this-which：this與which可用以代替前面提過的整件事情，但this所引導的是獨立子句，要加and或but，而which所引導的是從屬子句。
例：
1. Global food production has increased, and this enables more people to eat better.
2. Global food production has increased, which enables more people to eat better. (上列兩句this與which指“Global food production has increased”整句的意思)
問題思考：
1. S+VP, and this+S+VP.
2. S+VP, which+S+VP.
