请教有个句子 不理解 Airlines can make special offers that are sometimes cheaper than train tickets.There are also shuttle and commuter flights between some major cities that are close to each other.'请问这两个句子中that 是起什么

请教有个句子 不理解 Airlines can make special offers that are sometimes cheaper than train tickets.There are also shuttle and commuter flights between some major cities that are close to each other.'请问这两个句子中that 是起什么 线性代数有个问题不理解, 有个英语句子不理解some birds aren’t meant to be caged这里的mean（meant）什么意思 划线句子不理解! The meeting being held now is of great importance我现在是新概念2的水平,不理解这句子是个什么结构?是否有省略的部分 有个句子不理解,Many documentary cover science sucjects in great depth while also including some clever story telling plus the human interest aspect.telling plus 请教这个线性代数的定理.这个定理2能给个过程证明吗?或者解释下,我不理解. 有个英语句子不理解帮我看看your sister passed me in her new car ,driving at geat speed.driving是动名词么为什么要用ing?这个词在句子是什么成分?能不能能用其他词替换? 有个德语句子不理解,请求帮助.句子如下：Unverzichtbar nennt es Tom Doctoroff,Nordostasien-Chef bei der Werbeagentur Thompson,dass die in China aktiven Firmen ihre Kundinnen kennenlernen. 请看下这句句子是有矛盾,请帮忙翻译下（其中的they指谁）Airlines often have problems with business passengers because they are always used to being in control. 请教2个句子修改病句1.他的病症一直没有完全康复.2.有没有动脑筋是考出好成绩的重要原因.请教如何修改,请先说明问题所在,再说明改法及改后的句子.谢谢! 阅读中的相互照应,两个句子或词有什么关系我不理解. 我在做英语阅读的时候,有个不理解的句子,He still needs six months of growth before he hits ful size.怎么翻译,尤其是hits ful CHINA SOUTHERN AIRLINES是不是指中国南方航空?我要出国,但机票有好多都看不懂! 三题都请教一下,不知道怎么做.不理解. 有个英语单词不理解,refrigerator是什么意思,是可数名词还是不可数名词? 继承法意见46条怎么理解阿,举个例子,不理解婴儿怎么有继承人. The airlines plane flew almost nine kilometers above the ground.这个句子中哪里表示出是紧贴地面?