【单选题】Shall I lock the lab before I go home? __________. I’ll check it myself later.
【单选题】-'I’m afraid I must be going now. I ’ 11 come to see you before long.
【单选题】—Shall I lock the lab now before I go home? —________.I'll check it myself later.
【简答题】I didn't go to see the film, because I ______ (see)it before.
【单选题】零件图中直线的画法要求是要画的直而()。