应该做某事；被期望干某事
be at pains to do sth───努力做某事
be liable to do sth───有可能做某事
be hard put/pushed to do sth───被迫做某事
be supposed to be sth/have done sth───应该做某事
not one to do sth───不做某事的人
the better to do sth───做某事更好
not sb's place to do sth───不是某人做某事的地方
be nothing to do with───与…无关
be short on sth───缺少某物