Question

SAT语法题

The swiftest animal on earth, the cheetah can reach a top speed of about 70 miles per （(hour, it can)） maintain that speed for no more than 300 yards

答案是 hour but can 请问为什么不能是 hour,however,it can

Answer 1

but 并列的是 两个谓语 前面已经有主语 the cheetah.
however表示比较松弛 的 转折，
而本句 的 两个谓语 的内容 是紧凑的，所以不能用however。

Answer 2

but 是连词可以连接两个分句； however是副词，不可以连