A: 已休學滿二學年，若需再提出延長休學申請，依據《國立清華大學學則》第65條相關規定：

研究生保留入學資格、繳費、註冊、選課、學分抵免、更改成績、請假、休學、復學、雙重學籍、雙學位、開除學籍等規定，比照學士班相關條文規定辦理。
惟博士班學生休學累計以二學年為原則。因重病並持有健保局特約區域醫院以上證明，或特殊事故檢具相關證明者，經系務、所務或學位學程會議通過，報請教務長核准後，得延長之。其休學年限總累計至多以六學年為限。如因懷孕、分娩或為撫育三歲以下幼兒者，得檢具證明申請休學，不計入休學年限。

因此，若您要再申請延長休學，需同時檢附以下文件：

1.個人書面說明（請清楚敘述延長休學原因與需求）。

2.指導教授支持說明並簽名。

3.醫院證明（健保局特約區域醫院以上之診斷證明文件）。

上述文件繳交電子檔，以便納入本學程委員會會議中進行討論。

A: According to Article 65 of the "National Tsing Hua University Academic Regulations" regarding applications for extending a leave of absence after the initial two-year limit:

The regulations for graduate students concerning the preservation of admission eligibility, fee payment, registration, course selection, credit transfer, grade changes, leaves of absence (including suspension and resumption of studies), dual enrollment, dual degrees, and dismissal are handled in accordance with the relevant provisions for undergraduate students.

However, a leave of absence for doctoral students is, in principle, limited to a cumulative total of two academic years. For students suffering from a serious illness (with documentation from a regional hospital or higher contracted by the Bureau of National Health Insurance) or those with special circumstances (with relevant supporting documents), an extension may be granted upon approval by the Department, Institute, or Degree Program Committee and subsequent authorization by the Vice President for Academic Affairs. The total cumulative leave of absence period is capped at six academic years. Periods of leave taken due to pregnancy, childbirth, or childcare for children under the age of three (with supporting documentation) do not count toward this cumulative limit.

Therefore, if you wish to apply for an extension of your leave of absence, you must provide the following documents:

1. A Personal Statement: Please clearly describe the reasons and necessity for extending your leave.

2. Support Statement from Advisor: A written statement of support signed by your advising professor.

3. Medical Certification: A diagnostic certificate issued by a regional hospital (or higher) contracted by the National Health Insurance Bureau.

Please submit the electronic files of the aforementioned documents so they can be included for discussion in the upcoming Degree Program Committee meeting.