这几个词为什么要加sWhich seasons do you like best?The days are long and th nights are early.seasons,days,nights,为什么要加s

这几个词为什么要加sWhich seasons do you like best?The days are long and th nights are early.seasons,days,nights,为什么要加s 高中英语必修3 unit4 the oceans and seas完整句：the continued presence of water allowed the earth to dissolve harmful gases and acids into the oceans and seas.the oceans and seas.两次都是不可数,为什么还加S? seven seas forever翻译这是什么意思,. 这几个词为什么要加s1,It rains sometimes .2,It snows sometimes.3,The sun shines every day .rain ,snow ,shine ,为什么要加s 我只写了几个音符为什么要加引号 There were two small rooms in the house,( )severed as a kitchen.A the swhich B the smalmaller ofwhich 为什么选B seas是什么意思? coral seas 在变换成第三人称单数时surf为什么直接加s?而leaf 和knife为什么要变ves?我也知道这几个词不是同类.但是为什么会这样变?什么道理? 单词加est和iest什么意思?什么词要加?比如cheapest friendliest这些词为什么要加iest或est?加了后词意有什么变化?是某几个词的固定变化还是某一类词需要加? 介词后面的动词为什么要加ing?一定都要加ing么?举几个例子吧 swim的现在分词为什么要加ming而不是直接加ing,这样的情况有几个 造句加几个词填空,要全部回答 谁能帮我打出这几个字?（要加符号） That the seas are being overfished has been known for years句子结构分析我知道That the seas are being overfished 作主语 如果不要that 光是the seas are being overfished 能不能作主语 为什么？the seas are being overfished 是 印度国土面积小于俄,加,中国等,为什么耕地面积大于这几个国家 我只写了几个音符答案文章的题目为什么要加引号? If all the seas were one sea 这首英文诗的中文翻译