—Whatdidtheguardsaytoyoujustnow?—Hewarnedus

問題詳情：

—What did the guard say to you just now?

—He warned us ________ any farther. There's danger ahead.

A. didn't walk  B. not to walk  C. walk  D. to walk

【回答】

B

知識點：非謂語動詞

題型：選擇題