试题题干
Fill in the blanks with an item as required.
With a modal auxiliary:
I wonder why they haven't arrived yet. I told them how to get here but perhaps I have given them a map.
参考答案
试题解析
本题考查情态动词。由题干可知haven't arrived yet：他们还没到，所以have given them a map：给他们地图，推测是本应该给他们地图用should/ought to have done。
句意：我想知道他们为什么还没到。我告诉他们如何到达这里，但也许我应该给他们一张地图。