情态动词表推测 — 英语词汇题
题目
根据句意，用 can't / might / must 填空（每词限用一次）。
1. The library is closed at night, so the librarian ______ be working there now.
2. Mary has lived in Beijing for twenty years, so she ______ know the city very well.
3. I'm not sure where Jack is. He ______ be in the music room, or maybe in the art room.