The following is an example of one page out of the Employee Handbook, Annotated. The text in blue italics is the "annotation." The annotations are instructions and information to you regarding the paragraph immediately preceeding (above) the annotations.
All offers of employment are contingent on verification of your right to work in the United States, as required by the Immigration Reform and Control Act of 1986. Upon receiving a conditional offer of employment, you will be asked to provide original documents verifying your right to work and to sign a verification form (form I-9) required by federal law. If you cannot verify your right to work in the United States, Icare Optometry may be obliged to revoke the offer of employment.
New employees are introductory employees for the first 90 days of employment. During this period, you will have the opportunity to learn your new position and see whether you enjoy your employment here. The Office will use this period to determine whether you are able to meet its expectations. Introductory periods may be extended for business reasons or because of approved absences taken by the employee. During your introductory period you will not earn vacation time or sick time or otherwise be entitled to employee benefits. Except where otherwise provided in this Employee Handbook, only "regular" employees (those that are no longer "introductory") are eligible for benefits.
It is critical that you not refer to a "probationary" period. Probationary periods, in which employees are told that they can be terminated at any time, have often been construed to create "with cause" employment once the probation is over. And do not identify the post-probationary employment as "permanent." A better term is "regular" as this does not imply anything.
If an employer provides paid vacation it may, but does not have to accrue during an introductory period. But, if it does accrue during the introductory period (e.g. it is retroactive to include this period) and an employee, for any reason, terminates employment during the period, prorated vacation pay must be paid at the time of termination.