Next, you're going to create a "choose your pet"-field. There are a number of widgets for selection, but in this case want to force the user to select one pet and one pet only. Therefore, you are now going to select the radio button tool. Draw a square for the first radio button and name it "30 Pet" (in the Name field of the dialog that pops up).
ctrl+shift as you clone for that perfect alignment...
Click Close. Now, hold down the ctrl-key and drag the radio button to where you want the second radio button to be. Release the mouse button and voila! You now have two radio buttons which belong to the same family (=checking one will de-check the other) since they have the same name.
TIP: There's a best way in Acrobat Professional when creating multiple fields where only the name differs. Create one field to use as a template, with all the right check boxes and colors, and duplicate it.
TIP: Don't forget that you can copy and paste multiple fields between PDF files. Such an insight might save you hours of work...
Double click the left radio button and set the Export Value of the Options tab to "Cat".
In the same manner, set the right one to export the value "Dog". Finally, create an address field: Using the text field tool, draw a rectangle that fits right into the "Address"-field of the form. Set the Name of field "20 Address", then switch to the Options tab and check Multi-line.
