"to have," is rendered "could" in Mar 14:8, "she hath done what she could," lit., "she hath done what she had." See HAVE.
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"to have strength," is translated in Mar 14:37 "couldest thou not." See ABLE.
Notes: (1) Emblepo in Act 22:11, lit., "I was not seeing," is translated "I could not see." See BEHOLD.
(2) See CAN, when not used as part of another verb.