This question is best asked in the Microsoft Excel newsgroup.
I'm assuming you mean having one word atop another in the same cell. You would use ALT+ENTER to create the new line in the same cell.
So you would type basic ALT+ENTER salary to get:
basic
salary
all in the same cell.

Signature
Greg Collins [InfoPath MVP]
Please visit: http://www.InfoPathDev.com
how do i use excel to write a words e.g basic salary appearing in the same
cell.