Before the 1970s the slide rule, or slipstick, was as common as the typewriter or the mimeograph machine.
Before the 1970s the slide rule, or slipstick, was as common as the typewriter or the mimeograph machine.
1970年代之前，计算尺跟打字机和油印机一样，随处可见。
Before the 1970s the slide rule, or slipstick, was as common as the typewriter or the mimeograph machine.
1970年代之前，计算尺跟打字机和油印机一样，随处可见。