Grandma served sandwiches and biscuits to the children on paper plates.

辨认主题句：Choose the best topic sentence from the four options below. Write the corresponding letter of your choice on the answer sheet.A.Culture refers to the pattern of human activity.B.Culture is the invisible bond which ties people together.C.Cultural differences create diversity as well as conflicts.D.Culture is represented by the art, literature, language, and religion of a community.

辨认主题句：Read the following paragraph and underline the topic sentence.Our oceans are in more trouble than ever before due to the flow of plastic into the sea. Everything from plastic bottles to bags ends up in our oceans each year. Traveling on ocean currents, this plastic is now turning up in every corner of our planet. It is even being found in the deepest part of the ocean and trapped in Arctic ice. Our oceans are slowly turning into a plastic soup, and the effects on ocean life are devastating. Plastic pieces of all sizes choke the stomachs of creatures who mistake them for food, from tiny fish to whales. Plastic is now entering every level of the ocean food chain and is even ending up in the seafood on our plates.

辨认主题句：Read the following paragraph and choose the best topic sentence from the four options that follow. Write the corresponding letter of your choice on the answer sheet.Insect bites are not just an annoyance, but can come with serious consequences. People frequently use chemicals to protect themselves from insects, especially from mosquitoes (蚊子). However, these chemicals can have many unpleasant side effects, for both humans and the environment. Recently, there has been a lot of interest in non-chemical mosquito bite protection. A good candidate would be graphene (石墨烯)-a material made of carbon in very thin sheets that is already being used on clothes for various other applications. In a paper published in Proceedings of the National Academy of Sciences, researchers showed that graphene can provide a two-fold defense against mosquito bites. The ultra-thin yet strong material acts as a barrier that mosquitoes are unable to bite through. At the same time, experiments showed that graphene also blocks chemical signals mosquitoes use to sense that a blood meal is near, blunting their urge to bite in the first place.A.Researchers have recently published a paper on mosquito bite protection.B. Graphene blocks the signals that mosquitoes use to identify a blood meal.C. Mosquitoes serve as one of the most important carriers for many diseases.D. Graphene enables a new chemical-free approach to mosquito bite prevention.

Read the following paragraph and cross out TWO irrelevant sentences.For a long time a diverse population of Native American tribes prospered on the rich lands of California. Before European settlers arrived, an estimated 300,000 native people lived in small villages throughout the area. Some Native Americans are still living in California today. Contact with the new settlers brought about serious disruptions to the native way of life. The Gold Rush of 1848 brought still more devastation. Violence, disease and loss brought by the European settlers overwhelmed the tribes. By 1870, an estimated 30,000 native people survived in the state of California, forced to live on without access to their homelands. A professor of Native American Studies was interviewed about the European idea of land. The native tribes of California lived by hunting and gathering the fertile resources of the land. Their culture and religion place them in the role of caretakers not owners of the land, preserving it for the future.

Write a letter of invitation to your friend Sam based on the following situation.You are a volunteer at the Tourist Information Center. Ask Sam to join you during the summer holidays. Explain why more volunteers are needed, what the job responsibilities are and what qualifications volunteers should have for the position. Please sign your name as Li Fei. (150-200 words)

Choose the best topic sentence from the four options below. Write the corresponding letter of your choice on the answer sheet.

Read the following paragraph and choose the best topic sentence from the four optionsthat follow. Write the corresponding letter of your choice on the answer sheet.Has it ever occurred to you that your mind has in store more than you could imagine?Just think about all the phenomena that appear in your mind without you willing them there.Take dreams as an example. You don't command them into being, yet your dreams emerge from somewhere. Memories act the same way. You're in the kitchen preparing soup and remember a day from childhood when your family was eating steak. You didn't summon that memory. It showed up on its own. Other types of thoughts also turn up without help. You're sitting in traffic when the answer to a computer problem hits you. How did that happen? You weren't thinking about the computer problem, but your mind created the thought and somehow pushed it into existence. Those dreams, memories, and thoughts didn't come from outside of you. You generated them through means hidden from you.

Louisa May Alcott is as much of a well-known and well-respected household name as Mark Twain even for nonreaders. (periodic sentence)

Reading about emotional intelligence isn't enough. It won't make one more emotionally intelligent overnight. (simple sentence)