excell coding problem (1 Viewer)

[dredding]

hi all
i am new to vba but what i am trying to do is find a time and then add three rows under that. i have columns b and d as time format. but my time fall in column b or column d or between the two. as per example

b d
7:00 10:00
6:00 7:00
5:00 8:00

i am thinking it should be a if statement but not sure how to code it.

thanks for any advice on this.
dredding