1. It was only … fifth of July, and no meeting was fixed with Ann until … ninth. 2. Jill walked straight up to her former friend, kissed her cheek, and … two settled down on a sofa never sat on since the hotel's foundation. 3. He'd catch … two o'clock train back to New York. 4. She is quite aged for … seventy, isn't she? What I would call … old seventy. 5. The letter bored him, and when it was followed next day by another, and the day after by … third, he began to worry. 6. Mike looked at his uncle with disapproval when he took … second piece of cake. 7. He walked along thoughtfully. He wasn't going to to be one of … lucky ten who were going to be taken back. 8. “Miss Lucy will be … second mother to the children,” she said. 9. They talked of … thousand things, and they all talked at once. 10. Jack looked at her sideways, and placed … second piece of ham in his mouth. 11. The phone rang almost immediately … third time. 12. The phone, ringing for … fourth time, interrupted his thoughts. 13. … three times I have already done that. Everything! Then this time will make … fourth. 14. That question, too, he had asked himself … thousand times. 15. Once more he had used the service stairs from … eight floor to … ninth.
29. Read and translate Text 4.2:
The History of Computer Technology
The evolution of digital computing is often divided into generations. Each generation is characterized by dramatic improvements over the previous generation in the technology used to build computers, the internal organization of computer systems, and programming languages.
First Generation Electronic Computers (1937-1953). These machines used electronic switches, in the form of vacuum tubes, instead of electromechanical relays. Electronic components had one major benefit, however: they could “open” and “close” about 1,000 times faster than mechanical switches.
Software technology during this period was very primitive. The first programs were written out in machine code, i.e. programmers directly wrote down the numbers that corresponded to the instructions they wanted to store in memory. By the 1950s programmers were using a symbolic notation, known as assembly language, then hand-translating the symbolic notation into machine code. Later programs known as assemblers performed the translation task.
Second Generation (1954-1962). Electronic switches in this era were based on discrete diode and transistor technology with a switching time of approximately 0.3 microseconds. Memory technology was based on magnetic cores which could be accessed in random order, as opposed to mercury delay lines, in which data was stored as an acoustic wave that passed sequentially through the medium and could be accessed only when the data moved by the I/O interface.
Third Generation (1963-1972). The third generation brought huge gains in computational power. Innovations in this era include the use of integrated circuits, or ICs (semiconductor devices with several transistors built into one physical component), semiconductor memories starting to be used instead of magnetic cores, microprogramming as a technique for efficiently designing complex processors, the coming of age of pipelining and other forms of parallel processing, and the introduction of operating systems and time-sharing.
Fourth Generation (1972-1984). Entire processors fitted onto a single chip, and for simple systems the entire computer (processor, main memory, and I/O controllers) could fit on one chip.
Developments in software include very high level languages such as FP (functional programming) and Prolog (programming in logic). Compilers for established languages started to use sophisticated optimization techniques to improve code, and compilers for vector processors were able to victories simple loops (turn loops into single instructions that would initiate an operation over an entire vector).
Fifth Generation (1984-1990). The development of the next generation of computer systems is characterized mainly by the acceptance of parallel processing. Until this time parallelism was limited to pipelining and vector processing, or at most to a few processors sharing jobs. The fifth generation saw the introduction of machines with hundreds of processors that could all be working on different parts of a single program. The scale of integration in semiconductors continued at an incredible pace - by 1990 it was possible to build chips with a million components - and semiconductor memories became standard on all computers.
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