原文You can choose a mode only if you can choose legal targets for that mode. Ignore the targeting requirements for modes that aren't chosen. For example, you can cast Ojutai's Command without targeting a creature spell provided you don't choose the third mode.
原文As the spell resolves, follow the instructions of the modes you chose in the order they are printed on the card. For example, if you chose the second and fourth modes of Ojutai's Command, you would gain 4 life and then draw a card. (The order won't matter in most cases.)
原文If all targets for the chosen modes become illegal before the Command resolves, the spell won't resolve and none of its effects will happen. If at least one target is still legal, the spell will resolve but will have no effect on any illegal targets.