we have to be careful how we do this讲解一下

阅读下面的短文,在空白处填上适当的词,使短文在意义和结构上完整(一空一词).Saving WaterWater is important for us.We drink it every day.We use it to cook and wash things._____ water ,we cannot live.But we have to be carefu We have to be together forever We have to be ( ) in the library We have no need to be afraid of them.这是什么结构HAVE TO BE?是什么 英语小作文 关于读书Direction：For this part,you are required to write a composition on the topic：On Reading Books.You should write at least 120 words following the outline given below：1.Books serve different purposes.2.We musr be carefu The weather of these days is really bad.It’s foggy and there is haze in the air.So,we can’t see the things very far.Every morning,when I pull back the curtain,I only can see the building dozens miles away.When I go to school,I must be very carefu to,have,be,the,library,do,we,quiet,in(?) We have to be quiet in the library改为祈使句 we have to be up early in the morning We do not have to be a___ of catching SARS We have to be ____ about our chances of winning. we all have to learn about love and be loved . we have an art() to be an artist why i must we have to be alive? we have to buy a ticket to here还是we have to buy a ticket to be here? we have to be careful how we do this这句中 how we do this是什么成分? 翻译 you have the right to be happy we enable you to be happy life is never meant to be easy,so we have to be strong.right?