一、简单句常见的五种基本结构
1.主＋谓
I went to school at 9：00.
2.主＋系＋表
The food smells delicious.
3.主＋谓＋宾
He hopes to fly to the moon.
4.主＋谓＋间宾＋直宾
He gave me a pen.
5.主＋谓＋宾＋宾补
The boy wished his father to buy a bike for him.
超出这些简单句的范围之外的句子我们成为复杂句.复杂句的特点是句子冗长,大多数句子由20个以上单词组成,很多句子超过40个单词.另外结构复杂,频繁使用并列复合句、多重复合句等复杂句式
如：
Automated techniques to measure these characteristics and verify a person's identity infallibly are attracting widespread attention in these days of increased use of credit cards and e-mail.
分析：该句主语是automated techniques,谓语是attract,宾语是attention,in these days of increased use of credit cards and e-mail在句子里起时间状语的作用.
意思是说：在信用卡和电子邮件越来越多地被使用的今天,用来测量这些特性和确认人的身份的自动技术吸引了广泛的关注.