英语翻译这把刀是我见过的最快的一把今天比昨天暖和The boy is short(同义句）Shanghai is lar

这些帽子中,我最喜欢这一顶 Of all these hats I like this one best.
这把刀是我见过的最快的一把 This is the sharpest knife I have seen.
今天比昨天暖和 Today is warmer than yesterday.
The boy is short(同义句）The boy is not high.
Shanghai is larger than any other cities in China (变为同义句）Shanghai is the largest city in China
The red one is larger than the green one(对划线部分提问）The red one 划线
Which is larger than the green one?