Ответ:

1 - wrote to you, 2 - reply sooner, 3 - replying sooner, 4 - tell you that.../about...? 5 - what! 6 - guess what (happened..) 7 - news! 8 - know that..?

9 - thing, 10 - about (+ing)? 11 - could.. 12 - don't you/we..? 13 - if you/we could.. 14 - we/you could..