Lesson 5 (Oct. 13) Comparisons

1. Lesson 5 (Oct. 13)Comparisons Comparing dimensions, properties and quantities.

2. Comparatives • Sentences that compare two things: …… comparative (adjective -er) ‘than’………. • x is longer than y. • y is shorterthan x. • The Intel Pentium 4 is fasterthan the Intel 80486. • Another comparative form: ………more __________ than…… ……… less ___________than …… • Hydrochloric acid is more dangerousthan citric acid. • Citric acid is less dangerous than hydrochloric acid. • Sea water contains more saltthan fresh water.

3. Comparatives – more examples • …… comparative (adjective -er) ‘than’………. • A meter is longer than a yard. • The Indian Ocean is deeperthan the South China Sea. • In summer Taipei is hotterthanPuli. • The streets of Puli are narrowerthan the streets of Taipei. • Taipei is a busier citythan Kaohsiung. • Microwaves are shorterin wavelength than radio waves. • The transistor was invented laterthan the vacuum tube. • User the –er form for short adjectives: • longer – longer • short – shorter • narrow – narrower • deep – deeper • tall – taller • big – bigger • fat – fatter • hot – hotter • busy – busier • late – later

4. Comparatives • Look up a dictionary for the comparative form:

5. Comparatives

6. Modifiers in Comparison Statements • As in all English sentences, comparison statements can contain modifiers to give more information or more precise meaning. • Other examples: • Gold is heavier in atomic weight than iron. • The Fourier transform is easier to understand than wavelet transform. • Men are taller on average than women. • Microwaves are shorterin wavelength than radio waves. Without the modifier, the statement is grammatically correct but not very meaningful.

7. Another Comparative Form: more/less ___ than • Examples: • Hydrochloric acid is more dangerousthan citric acid. • Citric acid is less dangerous than hydrochloric acid. • This form is used for most adjectives. • In technical writing, this form is preferred.(except short adjectives) YES: • The Van der Pol oscillator is more stablethan an LC circuit. NO: • The Van der Pol oscillator is stablerthan an LC circuit.

8. Adjectives without –er comparative form • Whether to use –er form is actually complicated. Look up a dictionary and read more books/papers! no –er form given

9. Another Comparative Form: more/less ___ than • Never use the –er and “more than” forms together: • No, no, no! • The MOSFET is more commoner in both digital and analog circuits than the bipolar junction transistor. • Yes: • The MOSFET is more commonin both digital and analog circuits than the bipolar junction transistor.

10. The have ________ than Structure • What we saw was the structure: be___________ than • Car A ischeaperthan car B. • Car B ismore expensivethan car A. • Car A isless expensivethan car B. • The same statement can be written in another structure: have___________ than • Car A hasa lower price than car B. • Car B has a higher price than car A. nouns

11. The have ________ than Structure • Examples: • The Indian Ocean isdeeperthan the South China Sea.The Indian Ocean hasa greater depththan the South China Sea. • In summer Taipei ishotterthanPuli.In summer Taipei hashigher temperatures thanPuli. • The streets of Puliarenarrowerthan the streets of Taipei.The streets of Pulihavesmaller widthsthan the streets of Taipei. • Microwaves areshorterin wavelengththan radio waves.Microwaves haveshorter wavelengthsthan radio waves. • The transistor wasinvented laterthan the vacuum tube.The transistor hasa shorter historythan the vacuum tube.

12. The have ________ than Structure • This structure is an extension of structure 2 for describing dimensions and properties: • The Indian Ocean has an average depth of3,890 m.The Indian Ocean hasa greater depththan the South China Sea. • Water hasa boiling point of 100C.Water hasa higher boiling point than alcohol. • Microwaves havewavelengthsof 30 cm to 3 mm.Microwaves haveshorter wavelengthsthan radio waves. • The transistor has ahistoryof about 90 years.The transistor hasa shorter historythanthe vacuum tube.

13. Comparing Quantities with have ________ than • Countable quantities: • Building A has more rooms than Building B. • Building B has fewer rooms than Building A. • A hexagon has more sides than a triangle. • A triangle has fewer sides than a hexagon. • Uncountable or singular quantities: • Car A consumes more petrol than Car B. • Car B consumes less petrol than Car A. • Sea water contains more salt than fresh water. • Fresh water contains less salt than sea water.

14. Superlatives • When comparing with more than one things, the superlative form is used: … the _____-est … superlative of … ____-er than … … the most ______ … superlative of …more _____ than … … the least ______ … superlative of … less/fewer ____ than … • The Indian Ocean is deeper than the Pacific and the Atlantic. The Indian Ocean is the deepestoceanin the world. • Taipei is a busier city than all other cities in Taiwan. Taipei is thebusiest city in Taiwan. • The electronics group has more students than the communications and systems groups. The electronics group has the most students. • Hydrogen is the lightest gas. • Hydrogen has theleast atomic weight.

15. …not as ________ as ... • Instead of the more … than comparative form, one can also use the following equivalent form, but be careful when comparing nouns: