is entitled to basic pay under section 204 of this title or compensation under section 206 of this title; and

serves in a career field or skill designated as critical by the Secretary concerned.

A proficiency bonus may be paid under this subsection to a student who is enrolled in the Senior Reserve Officers’ Training Corps program even though the student is in the first year of the four-year course under the program. During the period covered by the proficiency bonus, the student shall also be entitled to a monthly subsistence allowance under section 209(c) of this title even though the student has not entered into an agreement under section 2103a of title 10. However, if the student receives incentive pay under subsection (g)(2) 1 for the same period, the student may receive only a single monthly subsistence allowance under section 209(c) of this title.

A proficiency bonus under subsection (b) may be paid in a lump sum at the beginning of the proficiency certification period or in periodic installments during the proficiency certification period. The amount of the bonus may not exceed $12,000 for each 12-month period of certification. The Secretary concerned may not vary the criteria or rates for the proficiency bonus paid for officers and enlisted members.

Proficiency in a designated critical skill for purposes of subsection (b) shall be subject to annual certification by the Secretary concerned.

A certification period for purposes of subsection (c)(2) shall expire at the end of the one-year period beginning on the first day of the first month beginning on or after the certification date.

Notwithstanding paragraphs (1) and (2), the regulations prescribed to administer this section shall address the circumstances under which the Secretary concerned may waive the certification requirement under paragraph (1) or extend a certification period under paragraph (2).

The Secretary concerned may require a member to enter into a written agreement with the Secretary in order to qualify for the payment of skill incentive pay under subsection (a). The written agreement shall specify the period for which the skill incentive pay will be paid to the member and the monthly rate of the pay.

The Secretary concerned shall require a member to enter into a written agreement with the Secretary in order to qualify for payment of a proficiency bonus under subsection (b). The written agreement shall specify the amount of the proficiency bonus, the period for which the bonus will be paid, and the initial certification or recertification necessary for payment of the proficiency bonus.

The Secretary concerned may pay incentive pay to a person enrolled in an officer training program to also participate in an education or training program to acquire proficiency in a critical foreign language or expertise in foreign cultural studies or a related skill designated as critical by the Secretary concerned.

Incentive pay may be paid under this subsection to a student who is enrolled in the Senior Reserve Officers’ Training Corps program even though the student is in the first year of the four-year course under the program. While the student receives the incentive pay, the student shall also be entitled to a monthly subsistence allowance under section 209(c) of this title even though the student has not entered into an agreement under section 2103a of title 10. However, if the student receives a proficiency bonus under subsection (b)(2) covering the same month, the student may receive only a single monthly subsistence allowance under section 209(c) of this title.

In this section, the term “critical foreign language” includes Arabic, Korean, Japanese, Chinese, Pashto, Persian-Farsi, Serbian-Croatian, Russian, Portuguese, or other language designated as critical by the Secretary concerned.