there are two old books on the shelf,but _______ of them is useful.A.both B.all C.neitherD.none说明理由

there are some 还是there are two Most children have all their ''milk teeth by the time they are two years old.there are 20 teeth . there are two bears o-- there Li-Li:Hello,Bo-Bo!Bo-Bo:Hello,Li-Li!Li-Li:How are you?Bo-Bo:I'm fine,thank you.And you?求汉语意Li-Li:Very well,thanks.How many people are there in your family,Bo-Bo?Bo-Bo:There are three:Father,Mother and I.Li-Li:What is your father?Bo-Bo:He is a There are some radio for old man there are old computers改为单数 There are two workers in the room.One is old and the other is young.The young worker is the old wThere are two workers in the room.One is old and the other is young.The young worker is the old worker’s son.But the old worker is not the young worker 英文翻译：There are same two.和 There are fifty. Once there was a man with a two-years-old how many books are there on the shelf?N___,there are only some exercise-bo there are two workers in the room ,one is old and the other is young.the young worker is the old worker's son,But the old worker is not the young worker's father ,why?同志们,回答 There are two teachers in the room.One is old,the other is young.The young teacher is the old teacher's son .But theold teacher isn't the young teacher's father.Who is the old teacher ,then? there are two kinds of memory there are two chairs and a desk There are two farmers ( ) the apple trees There are two pictures ) the wall Are there d_ between the two pictures? There are four windows ( )the two doors.