Unit 4,Water cycle,Part I,Book 2-Unit 4,Communicative Activities,Introduction of Functions,You may express uncertainty like this:,You may express certainty like this:,Im not quite sure .,Im sure Ill be very much interested in reading your article.,More Expressions for Certainty & Uncertainty,Book 2-Unit 12,Im quite sure/ certain (that) Im absolutely sure/ certain (that) Im fairly sure/ certain (that) Im sure/ certain about Ive no doubt about Yes, Im one hundred percent sure. Yes, certainly/definitely/of course. Yes, without doubt. Yes, really! Yes, thats obvious.,Book 2-Unit 12,How to express certainty:,How to express uncertainty:,Well, its possible I suppose, but Im not really sure. Well, it might be, but I doubt it. Well, theres always a chance, but I have my doubts. Sorry, Im not sure. I cant make up my mind whether to do I cant decide Im not really/too sure about Im of two minds about I cant say for certain. I wouldnt be too sure about ,Book 2-Unit 12,Extra expressions of the same functions:,- I dont think there can be any doubt about/as to - There is no/very little doubt in my mind about/as to - Its/Thats my conviction - Im (quite) convinced - Its quite certain that,- Im afraid I cant be certain about - Theres some doubt in my mind about - Im not at all convinced/certain - One cant say with any certainty that - Theres still an element of doubt about,Book 2-Unit 12,Discussion,The unexpected always happens.,The most unexpected moment in my life,Learn to understand the cultural implications of this proverb and trying to find examples in real life in its support.,Book 2-Unit 12,The most unexpected moment in my life,Story Telling,Book 2-Unit 4,Interactive listening & speaking,Book 2-Unit 4,Wastewater treatment,Physical, chemical and biological processes for making wastewater suitable for human consumption and other purposes.,wastewater,99.9% water,0.1% waste,Why wastewater treatment?,Listen to a lecture given by an expert about wastewater treatment technologies. While you listen, take notes and complete the tasks on page 51.,Wastewater treatment,water molecules,Wastewater treatment plant,An engineering marvel,Sewer system,It connects millions of homes, businesses, industries, and institutions to a network of underground pipes which transports wastewater to the wastewater treatment plant before it is released to a river or lake.,Three major steps,Wastewater treatment plant,Preliminary step: mechanical processes separate large solids (sand, grit沙砾) and debris(残渣，废物) from the liquid Primary step: mechanical and biological processes further separate water from waste materials Secondary step: chemical processes kill remaining harmful bacteria,Natures processes of wastewater treatment and how it is different from the engineering processes in the wastewater treatment,Nature uses two steps only: 1. mechanical process: large solids and debris are separated from wastewater 2. biological process: bacteria, fungi and algae will eat away the remaining pollutants in the wastewater Notes: fungi is the plural form of fungus真菌 algae海藻 Nature does not use chemical process to kill harmful bacteria, fungi or algae, which consume pollutants in wastewater.,Book 2-Unit 4,Byproducts of wastewater treatment and their uses,Sludge: a kind of mud which can be applied to the farmland as fertilizer when it is dried. The expert calls it soil conditioner. 下水道的污泥,Feature of language for describing scientific and technological knowledge,Simple present tense High degree of certainty,Part II,Reading and Language Activities,Book 2-Unit 4,Pre-reading Task Comprehension Work Language Work,Outline,Book 2-Unit 4,Return to Menu,How much do you know about Singapore? (history, official languages, population, economy, etc.) 2. What else are you interested to know about this little city-state?,Pre-reading Task 1,Pre-reading Task 2,Sewage treatment, or domestic wastewater treatment, is the process of removing _ from wastewater and household _. It includes physical, chemical, and biological processes to remove physical, chemical and biological pollutants. Its objective is to produce an _ fluid waste stream (or treated effluent 废水) and a solid waste (or treated _) suitable for disposal or _ (usually as farm fertilizer). Using _ technology it is now possible to re-use sewage effluent for drinking water, although Singapore is the only country to _ such technology on a production scale in its production of NEWater.,Cloze,advanced sewage reuse implement contaminants environmentally-safe sludge,contaminants,sewage,environmentally-safe,sludge,advanced,reuse,implement,NEWater is the brand name given to _ water produced by Singapores Public Utilities Board. More _, it is treated wastewater (sewage) that has been _ using advanced membrane technology (膜化学技术) in addition to _ w