这个要看and前后的部分具体是什么了。假如and前后部分是平行关系,如:You're very nice and sweet....你人很好很贴心... nice跟sweet在这里是平行形容词,形容同一个主语,那么直接加就OK了,不用You're very nice and are very sweet.但是你的例句里不是这个情况,前面是系表结构,后面是be doing现在进行时。但是在 He is singing and dancing now. 他正在边唱边跳。在这句里,singing和dancing是平行的东西,就可以直接加,而不用加 be动词了。...
不一定,有许多情况都不需要一致的。例如:John is tall and plays the basketball well.You must be strong and healthy to qualify for the team.She has to be quick and aggresive to win this contes...