说出下列代数式的意义（1）3a+b：▁▁▁▁▁▁▁▁▁▁▁▁▁▁▁（2）a分之1+b：▁▁▁▁▁▁▁▁▁▁▁（3）（a-

说出下列代数式的意义（1）3a+b：▁▁▁▁▁▁▁▁▁▁▁▁▁▁▁（2）a分之1+b：▁▁▁▁▁▁▁▁▁▁▁（3）（a- I think ▁▁▁ a book is better than ▁▁▁ a film A read ,see B r 说出下列代数式的意义【1】a-b^2 【2】【a-b】^2 【3】a^2-b^2 【4】a-b分之a sally was ▁busy last week,a bit little b.a little of c.a bit 说出下列代数式的意义：【1】a+b 【2】(a+b ) 【3】a-b 【4】a-(b+c ) The idea ▁▁▁ they came up with was very good. A. then B. it The girl ▁▁▁ red is my little sister. A . in B . wears C . p 关于need的The doctor said he ▁▁▁▁an operation yet.A.need B.need 说出下列代数式的意义（1）a-b²； （2）（a-b）²；（3）a²-b²； （ Jenny▁▁▁▁(work)in a facory.her parents▁▁▁▁(work)in a hospita They ▁▁▁a bed,a desk,a chair,a sofa,a dresser and a bookcase that is ▁ interesting computer game.A.a B.an C.the D./