There are several ways and here is one approach:
Draw a tall rectangle approximately twice as tall as it is wide. Copy and
paste and move the copy to the right side of the first in such a way that the
left edge of the copy sits over the right edge of the original. Group them.
Drag out a slightly smaller rectangle and move it over the centre vertical
line. Specify 'no line' for your smaller rectangle and what you have is a
white block hiding the middle part of the middle vertical line. Now create a
text box and write the character A in it . Specify 'no line' and 'no fill'
for the text box and move it on top of your box.
When you are happy with the shape, font, line thickness of your box, group
the lot together. Copy, paste and move the copy, once again making the right
edge of the first completed box equal the left edge of the copy. Group them.
Continue copy, paste , move and group until you have the number of boxes you
want in your row.
Now you have to back and change your letters.
