this is an a（ ） clock 如何填空?

Is this （）umbrella?A.an B.a C./ This is an ）tiger. there is ____（a/an）“o” in this word. there is ____（a/an）“r” in this word. this is an a（ ） clock 如何填空? a和an的用法This is( )book This is( )eraser This is( )Englishbook This is( )dictionary This is( )notebook This is( )encyclopdia 在（ ）填a或an （）1.This is () pear and that is () apple.A.a,an B.a,a C.an,a this is a(an) university?a 还是an? 1.填写一个字母,是算式两边相等.E+J=G+（ ）2.观察例子,注意字母的发音,自己试试读字母,在横线上填写a或an.例如：This is a K.This is an F.This is an A.This is a P.This is S.This is Q.This is H.This is E.第一题 It's ten o'cloc.The shop____now.It usually___at nine in the evening.A.closes closes B.is closedIt's ten o'cloc.The shop____now.It usually___at nine in the evening.A.closes;closes B.is closed; closes C.is closing;is closed D.closes;is closed My father‘s birthday is October 8th （一般疑问句 ）__ __ __ birthday October 8thIt’s Marth 21st（提问）__ __ it?We have an Art Festival every year(提问)__ __we__ every year?He watches TV at 8 o'clock in the evening（对at 8 o‘cloc This is Mike T-shirt.（ ） ----- ----- A B I am an policeman.This is Mike T-shirt. （ ）----- ----- A BI am an policeman. （ ） --- -- A B不懂. This is a banana and that is an What is this怎么回答,是It is+a/an This is an eraser That is aThis is an eraserThat is a plate变复数句 This is ______apple and that is _______banana.A.This is ______apple and that is _______banana.A.a.an B.an.an C.an.a D./ ./ This is an（ ）（interest） story. Is this an egg?