when I opened the window,I hearsome birds_________in the tree A.to sing B.singing C.sang D.sing为什么选B.这是过去时而b是进行时啊

When I opened the door,I (get) a big surprise I can easily find the best price when I do some shopping online wi( )your Help I got surptised when I opened the u_____ gift mu mother sent me.I got surptised when I opened the u_____ gift my mother sent me. i got surprised when i opened the u__gift my uncle sent me I got surptised when I opened the u_____ gift mu mother sent me. I was going to open the door when it opened of itself.什么意思? 连词成句 close,when,the,I,to,was,it,getting,opened,door I had hardly opened the door when he rushed inhad 在这里有什么作用? WHEN THE PIE WAS OPENED怎么样 the moment 的用法when i opened the door the momemt the scale fell from my eyes可以说成when i opened the door,the moment ,the scale fell from my eyes when I opened the door.I found a dog _____in the snow.A.lie B.lying C.lay The boy __English on the radio when I __ his door.A.was learning,opened B.is learning ,opened我觉得两个都可以,究竟改选哪个呀? When i am geting close to the door,the door opened.这个句子是一个表示门 主动开的句子.我不明白为什么后面是opened. When I opened the book ,I found several ( ) pages.A.disappear B.going C.lost D.missing I found my students (sitting) at their desks,(reading) attentively when I opened the door.求讲解.急. Help!I had hardly opened the door when I he hit me.I had hardly opened the door when I he hit me.这句话中的hit 用不用加s 为什么I had hardly opened the door when he hit me.没有I 的 sorry I was listening to the radio ____ wI was listening to the radio ____ washing clothes.A.asB.whileC.the timeD.when 89.when I was about to go out,the door opened----------89.when I was about to go out,the door opened----------A.of itself B.by itself C.oneselfD.for itself