31.   This model of typewriter is efficient and durable， economical and practical for middle school students.

    這個型號的打字機對中學(xué)生來說，高效、耐用、經(jīng)濟、實惠。

    32.   The computer we produced is characterized by its high quality， compact size， energy saving and is also easy to learn and easy to operate.

    我們生產(chǎn)的計算機其特點是質(zhì)量好，體積小，節(jié)能，而且易學(xué)好用。

    33.   They are not only as low-priced as the goods of other markers， but they are distinctly superior in the following respects.

    它們不但和其它廠家的產(chǎn)品一樣低廉，而且在以下幾個方面有其獨特的優(yōu)越性。

    34.   You will get a 30% increase in production upon using this machine and also it allows one person to perform the tasks of three people.

    一旦使用該機器，你們將會增產(chǎn)30%，而且一個人可以頂3個人使用。

    35.   This product will pay its own way in a year.

    該產(chǎn)品一年就可收回成本。