I must go now.It's late.为什么用must而不用have to?

I must go now.It's late.为什么用must而不用have to? It's 6:30 p.m.It's time to go home.I must l__ now i must go to school now同义句It's time 空格 空格 空格go to school now. It's too late.I must go home right now.[同义句]回答：It's too late.I must go home （ ）（ ） it is too late now,i must go to sleep I must go now.It ____late(get)完形填空 I'm sorry.I ---go now.It's getting too late.横线上是填must 还是 have too?说下理由 1:Best wishes to you!2:Can i have some more soup?3:It's late.I must go now. —It's getting late.I'm afraid I must go now.—OK.____ Asee youBgo slowlyCstay longer I must go no now, i must go to bed now.It's()eleven o'clock.A.at B.in C.on D.about 为什么这里用until什么意思?----it's 10 o'olock now ,i must go----it's raining outside,Don't leave until it stops I must go now 还是 I must going now --it's getting late.I'm afraid I must be going now.--OK.( )a.take it easy b.see you c.stay longer d.go slowly must go now.it's a___eight o'clock now.根据句子提示,完成句中所缺单词We must go now.It's a___ eight o'clock now.E____ you or I an wrong.It is a funny time _____(eat) breakfast.For us,it's very necessary _______(brush)our teeth every even -----it is 9o'clock now.i must go.-----it's raining outside.( ) leave until stops.to not not to do not not 为什么选c stops It's getting dark now.I'm afraid I _______ go.选用情态动词的适当形式填空must,needn't ,should ,may ,can ,have to,could ---It's getting late .I am afraid I must be off now ----_______!A Go slowly B No problemC All right