And she said boom – a sudden period of growth.

她说到了风靡一时——突然增长的一段时期。

In 1971, Leonard Riggio acquired the company, which set off a period of growth.

1971 年，伦纳德·里吉奥收购了该公司，开启了一段增长时期。

The US economy alone expanded by over 40% during the 1920s, one of the sharpest periods of growth in modern history.

仅美国经济在 20 年代就增长了 40% 以上，这是现代历史上增长最快的时期之一。