What started as a residential area for Chinese immigrants then turned into a centre for Chinese culture.
(1)句式分析：这是一个主从复合句。What started as a residential area for Chinese immigrants是一个主语从句，整句话的谓语是turned into。
What caused the accident remains unknown.
This book will show you what should be known by good teachers.
Our city isn't what it used to be.
Visitors can also spend hours just exploring the interesting sights，smells，and sounds of China.
(1)句式分析：这是一个简单句。主语是Visitors，谓语是can spend，hours是宾语，使用了“spend＋一段时间＋(in) doing sth.”句型。
(2)“sb. spends＋一段时间＋(in) doing sth.”句型表示“某人花费一段时间做某事”。如：
They spent three months touring Europe.
We spent hours studying the structure of leaves under the microscope.
It has a long and famous history，with the author Robert Louis Stevenson having spent much time writing there.
(1)句式分析：这是一个简单句。It是句子的主语，has是谓语，a long and famous history是宾语，后面是with的复合结构在句中作状语。
In summer，she usually sleeps with the windows open.
Do you know the lady with a baby in her arms?
She died with her son yet a baby.
He lay on the grass with his eyes looking at the sky.
With his hair cut，he looked much younger.
With a lot of homework to do，I can't go skating with you.
She knew that with him to help her，she could succeed.
All kinds of traditional Chinese herbal medicine can be found，too，and there are Chinese tea stores，where visitors can taste and buy varieties of Chinese tea.
(1)句式分析：这是一个主从复合句。主句是All kinds of traditional Chinese herbal medicine can be found，too，and there are Chinese tea stores，其中包含and连接的两个并列分句，where visitors can taste and buy varieties of Chinese tea是where引导的定语从句，修饰先行词stores。
This is the place where I was born.
She has got to the point where she feels that she cannot take it any more.
1． struck me most in the movie was the father's deep love for his son.
2．He sat on the grass with his sheep (eat) grass.
3．Students should involve themselves in community activities they can gain experience for growth.
4．I spend about 50 pounds a month just books.
5．Nowadays people are more concerned about the environment they live.
6．We live in a society exchanging presents is an important part of communication.
7．With so many problems (solve)，he will have a hard time.
8．With a boy (lead) the way，we found the place easily.
9．They sat together around the table，with the door (close)．
10．He stood there with his hand his pocket.
11．He fell asleep with all the windows (open)．
12．It took me two hours (do) the cleaning.
13． he needed was a job.
14．Pluck up courage to do you're afraid to do.
1．Watch out for the (poison) snakes.
2．The young man lay on the sofa with his arms (fold) and soon fell asleep.
3．Some children are likely to be naughty sometimes and it's difficult for them to settle down their study.
4．These colorful crayons are not suitable (use) in very hot weather.
5．Don't eat the foods (contain) too much sugar and fat, which will make you put on weight easily.
6．How could you turn such a good job when you have been out of work for months?
7． made her succeed later on was the kindness and consideration she showed to all her patients.
8．The old couple often take a walk after supper in the park with their pet dog (follow) them.
9．Can you think out a situation the word can be used?
10．China is not she used to be.
11．Charlie spent much time and energy (look) after his sick mother and his brother.