a/an/the

• Before almost all nouns, some way of specifying the noun is required.
• The most common words used are the and a/an.
  • a/an - one of many
  • the - specific one

• Examples:
  • A Windows computer crashed. (One of many Windows computers)
  • The Windows computer crashed. (Only one Windows computer)
  • The fastest CPU available is DEC's Alpha processor.
  • A programming language taught at this university is C. (One of many)
  • The programming language taught at this university is C. (C is the only one)

• `An' is used before a noun starting with a vowel sound.

• Examples:
  • Data in an EEPROM can be erased electrically.
  • He is an honest professor.
  • (!) This is a universal problem.
  • (!) This circuit uses an NPN type transistor.

When "the" or "a/an" is not needed

• Other words can be used instead of the and a/an.
• When words such as his, her, this and that are used, the or a/an is not necessary.

• Examples:
  • His hard disk has a capacity of 8 GB.
  • That circuit requires a power supply of 5 V to operate.
  • How many transistors are in that IC?

• When something is being referred to in general, instead of the or a/an the plural form of the noun is used.
• For countable nouns, the plural form usually just requires adding an `s' to the end of the word.
• For uncountable nouns, no change is necessary.
• Before an uncountable noun or the plural form of a countable noun, `a' or `an' never appears.

• Examples:
  • Windows computers crash frequently. (Windows computers in general)
  • When capacitors are connected in parallel, the total capacitance increases.
  • During compilation of a program, object files are created.
  • Current is created by the movement of electrons.
  • Gold is used inside integrated circuits.

• Before company and other names, the and a/an are not necessary.

• Examples:
  • Microsoft should have been split into two companies.

Quiz

1. There are _____ 200 statements in this program.
2. What is _____ square root of 36?
3. I bought _____ 60 GB hard disk for my computer.
4. Programming languages such as _____ C are high level languages.
5. CDMA is one of _____ technologies used in wireless communication.
6. Ethernet is _____ popular type of computer network protocol.
7. We measured _____ inductance of the coil we made.
8. _____ integrated circuits are very small.
9. There are nine AND gates in _____ circuit in this diagram.
10. We used _____ n-channel FET in our experiment.