Lesson 2 (Sep. 22) Introduction to Scientific Statements

1. Lesson 2 (Sep. 22)Introduction to Scientific Statements Basic sentence structure: Statements requiring thePresent Simple

2. Statements Requiring the Present Simple Tense • The present simpleis used for regular actions and regular processes: • He studies physics six hours a week. Regular action: He studies every week. • The crude oil then passes down the pipe-line. Regular process: The sentence implies that the oil passes down the pipe-line all the time. Regular action/process means periodic action or continual process.

3. Statements Requiring the Present Simple Tense • The present simple is used for factual andgeneral statements: • Water freezes at 0 Celsius. (fact) • Area equals length times height. (fact) • This type of devices requires a 5-Volt supply. (general) • An airliner cruises at about 30,000 feet. (general) • It is also used for theorems and definitions: • The induced electromotive force in a closed circuit (theorem)equals the time rate of change of the magnetic flux. • A Lie group is a differentiable manifold with a (definition)group structure.

4. Statements Requiring the Present Simple Tense • The present simple is also used for observations and in descriptions of experiments: • The liquid in the test-tube weighs 55 grams. • The filter paper then collects the impurities. • The temperature rises until it reaches 100, and remains constant after that. • From the figure, we can see that the diode breaks down at about-3 Volts. • General rule: Always use the Present Simple unless there are good or compelling reasons for using another tense.

5. Present versus Past Tenses • Past tenses are almost always reserved for describing past works, historical facts and results, etc. ZhoresAlferov, Nobel Lecture, 2000.

6. Present versus Past Tenses • Use present tenses to describe your present work or established facts. ZhoresAlferov, Nobel Lecture, 2000.

7. Form of the Present Simple it he she they we you I produce + S produce Verbs ending in ss, sh, ch, x, and o add es to the base they pass he passes they push he pushes they watch he watches they mix he mixes they go he goes These ending consonants are a part of the fricatives in English phonology. Verbs ending in yafter a consonant change y to ies they hurry he hurries they magnify he magnifies Verbs ending in yafter a vowel add s after y they obey it obeys they say he says

8. catches solidifies studies weighs compresses washes fixes employs travels flies passes turns explodes sticks Exercise: Put the Verbs into the correct form • He (study) biology. • The current (pass) along the wire. • This ring (weigh) 125 grams. • Sound (travel) at a speed of 333 meters per second. • Rain (wash) salt from the soil. • This factory (employ) thirty people. • This bird (catch) insects as it (fly). • Water (solidify) or (turn) into ice at 0C. • Glue (fix) or (stick) two surfaces together. • The down-stroke of the piston (compress) the mixture until it (explode).

9. Exercise: Put the verbs in brackets into the correct forms Around the earth there (be) a large area of gas which (form) the atmosphere. This layer of gas – or more accurately, gases – (provide) some of the chemical materials which man (need). The other raw materials (come) from the earth and the sea. About four-fifths of the atmosphere (consist) of nitrogen. The remainder (be) mostly oxygen. The other five gases (be) very rare and, in fact, (make up) less than 1 per cent of the total atmosphere. Although these gases (be) rare, at least two of them (have) common uses in the field of electrical lighting. Electric light bulbs usually (contain) argon. Neon (be) also useful because it (give) out light when an electrical current (pass) through it. forms is provides needs come consists is are make up are have contain is gives passes

10. Exercise: Fill in the blanks with the six verbs below. Use each verb-form once only. When sunlight strikes an object the colour of the object depends upon the wavelengths which the object _________. If, for example, grains of sugar ___________ equally all the wavelengths of the spectrum, the grains __________ white. If a surface reflects only the wavelength which produces red and ___________ the other waves of the spectrum, the surface _____________ red. Black is the absence of colour because black objects _______________ all the light of the spectrum. absorb absorbs appear appears reflect reflects

11. Exercise: Put the verbs into the Present Simple, and correct the mistakes in subject-verb agreement. To improve the capability of high frequency (HF) surface wave radar to suppress interference, an adaptive anti-interference technique areis evaluated by using sub-arrays in OSMAR2000 (Ocean State Monitor and Analysis Radar, manufactured in 2000). The authors proposeda scheme that suppressesthe external HF radio strong interference based on OSMAR2000 radar without increasing any auxiliary facilities, and some radar experiments wereare carried out by using a monopole as the main antenna and the other three vertical monopoles as auxiliary antennas. A preliminary study of an adaptive system with sub-arrays for the suppression of strong interference areis presented. The results of the study show that the technique workedworks well against the observed interference.

12. Exercise: Put the verbs into the Present Simple, and correct the mistakes in subject-verb agreement. The Yangtze River estuary is the main production area of Anguilla japonica in China, as well as the only existing fishery area for adult eels. Japanese eels are distributed in the main rivers and many tributaries from the Yangtze River estuary to the upper Jinsha River, which extend to nearly 3 000 km. However, their migration behaviors remains relatively unknown. We analyzed the biological characteristics of 153 specimens of silver eels collected from the Jingjiang section of Yangtze River between September and November, 2008, and tested the sagittal Sr/Ca ratios of 27 specimens. Among the 153 specimens examined, 85 were are female and 68 were are male, which translatestranslatedto a female-male ratio of 1:0.8. All biological parameters of females were are significantly larger than those of the male specimens. Of 16 females, 13 were are river eels and 3 were are estuarine eels, while of 11 males, 36.36% was are river eels and 63.64% was are estuarine eels. The analysis on Sr/Ca ratios for every growth layer group (GLG) indicatesindicatedthere was are no significant differences between second-age males and females. However, significant differences were are observed between the third-age, fourth-age, and migration-age male and female specimens. This was is likely related to the fact that second-age eels of both sexes stay in the same inhabitation waters; however, as they grow older, they move to different areas.