1.在if虚拟语气条件句的主句中用would,could,should,might+动词原形。一般总是用would不错，可以译为“就会”；有“可能会”、“也许会”之意时，用could, might较好；有“应该会”之意时用should 较好。如： If he had not been busy,he would/could/should/might have helped you.他不忙的话，会/可能会/应该/也许会帮你忙的。 2.在“命令、要求、坚持、建议”等词后的that从句中用should＋动词原形，should可以省去。
