Let's put it simply:

A paragraph: It's usually a general statement. For example, how long has the unit been, how does the unit make you feel, and how the leader cares.

paragraph 2: write down the work at this stage, what you learned, what you did, what you accomplished, what you did well, what you didn't do well, and what problems you had. (mainly to express that I have been qualified for this position through running-in, exercise and study during the probation period).

paragraph 3: write down the next work plan, which can be a concrete plan or a simple expression of determination. Finally, express your willingness to become a full member.