Does the number of bladders on bladder-wrack seaweed change with depth?主要是bladder-wrack 和 bladders 都是什么意思（在句子里的意思）!求人工翻译。

The number of the students in our school__about 1800.A.is B.are C.do D.does选哪个? [ ]of students [ ]to go to beijing universitya a number ,wants b a number ,wantc the number ,wantsd the number,want What's __________ people in Australia?A. the number of B. a number of C. number D. the population of （）students like singing the song A number of B a number of C thenumber of There are () stamp-collectors in our class A the number of B a number OF c NUMBERS D NUMBER OF ( )students( ) learning English hard.A.The number of;is B.The number of;are C.A number of;isD.A number of;are Look!( )children( )playing on the playground.A:The number of;are B:the number of;is C：a number of;are D:a number is a number of the number of the number of,a small number of,a number of. if y is the sum of 3x and 5 more than x ,by what number does y exceed A 2B 3C4D5E can not be determined the number of造句 the number of造句 the reciprocal of number the number of中文 the number of 是什么意思? the number of同义词 The number of students Number of the black