那是倒装。
一般陈述: The uses of adversity are sweet
逆境(苦难)的价值是甜美的；
苦尽甘来之意。
祸兮福之所倚 。
塞翁失马，焉知祸福。
Sweet are the uses of adversity.
常常是苦尽甘来。
Sweet are the uses of adversity.(William Shakspeare,British Playwriter)
苦尽甘来。(英国剧作家莎士比亚)
Sweet is the uses of adversity. --William Shakespeare, British Play writer
苦尽甘来。英国剧作家莎士比亚