理工类辅导资料：疑问句详解How many N are there ……
结构：
问句：How many 复数名词 are there in/on 名词?
答句：There is/are 单数（复数）名词 in/on 名词。
说明：此句型意为“在某处有多少…?在某处有…。”该句型中，many 修饰复数<名词>；又因本句型是 <疑问句>，故用 are there，不可用 there are.
How many seasons are there in a year? There are four seasons in a year.
一年有几个季节? 一年有四季。
How many days are there in a week? There are seven days in a week.
一星期有几天? 一星期有七天。
How many lessons are there in this book? There are twelve lessons in this book.
这本书里有几课? 这本书里有十二课。