Sec. 311.016.  "MAY," "SHALL," "MUST," ETC.  The following constructions apply unless the context in which the word or phrase appears necessarily requires a different construction or unless a different construction is expressly provided by statute:
(1)  "May" creates discretionary authority or grants permission or a power.
(2)  "Shall" imposes a duty.
(3)  "Must" creates or recognizes a condition precedent.
(4)  "Is entitled to" creates or recognizes a right.
(5)  "May not" imposes a prohibition and is synonymous with "shall not."
(6)  "Is not entitled to" negates a right.
(7)  "Is not required to" negates a duty or condition precedent.
Added by Acts 1997, 75th Leg., ch. 220, Sec. 1, eff. May 23, 1997.