※ 引述《ptt809 (成为对的人)》之铭言：
: 大家好，新年快乐，想请问2题
: 1.The entire department will have to work ________ because of the
: previous setback.
: (A)all harder (B)for the harder (C)for harder (D)all the harder
考词组 all the harder = harder
有听过 work hard 吧 - 努力工作
work harder - 更努力工作
: 2.I can't find my wallet anywhere. I guess I _______ it in the restaurant.
: (A) may leave (B) should have left (C)ought to leave (D)could have left
语气助动词
［would/could/should/might/...]
本题，用于单纯表示"猜测" – 也许、或许、可能
现在：我找不到包皮
过去：我"也许或许可能"把它留在餐厅
因为是描述过去，文法是 语气助动词＋现在完成式
AC先删。
"could" have +PP