Old computers were used to occupy one entire room , now , they only have the size of a box , even the size of a book .
Old computers used to occupy one entire room , now , they are only the size of a box , even the size of a book .
Old computers used to occupy one entire room , now , they are only the size of a box , even the size of a book .
Fix grammatical errors in this sentence: Old computers were used to occupy one entire room , now , they only have the size of a box , even the size of a book . Output: