First-level title, bold, centered, bold No.2, single line, 0.5 line before the paragraph and 0.5 line after the paragraph.

Graduation thesis, secondary title, No.3 bold center, single line, 0.5 line before the paragraph and 0.5 line after the paragraph. Third-level title, bold, fourth bold and left-aligned, single line, 0.5 line before paragraph and 0.5 line after paragraph. Four-level title, small four bold left alignment, single line.