He was so absorbed in his work that not a sound ______.

I’m leaving tomorrow.— Oh, what a pity! I won’t be able to see you offI __ a tele-conference the whole morning

在四线三格中占格相同的一组字母是 。

__________cleaning the yard and making up the beds for the old，we also read newspapers for them and had chats with them

I went hiking in Shanxi last year and lived in the hotels at nights________.