The first PCs.in kit form,分析句子高手帮忙!!

来源：百度知道 编辑：UC知道 时间：2024/05/25 00:29:03
The first PCs.in kit form,appeared in the mid-1970s,and by the mid-1980s machines such as the Apple Macintosh and those based on a PC first brought out by IBM in 1981 were popular throughout the world...
and by the mid...这里的by怎么理解??

by the mid-1980s
直到20世纪80年代中期
by...直到……

The first PCs.in kit form,appeared in the mid-1970s
第一台整机形式的个人电脑出现在20世纪70年代中期
and by the mid-1980s machines such as the Apple Macintosh and those based on a PC first brought out by IBM in 1981 were popular throughout the world...
直到20世纪80年代中期,像IBM公司于1981年推出的基于个人电脑的苹果电脑那样,类似的电脑已经风靡全世界。