My train arrives in Shenyang at seven o'clock tomorrow. The plane I would like to take from there ________ by then.
句意：我乘坐的火车明天7点到沈阳，到那时，我想乘坐的航班可能已经从那里起飞了。时间状 语“by then”意为“到那时”，常和将来完成时连用。因此，本题的正确答案为B。