One winter day ____, he saw the tracks of animals in the snow and observed that the appearance of each one was different.
A.while he hunting | B.while hunting |
C.while he hunt | D.while hunted |
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One winter day ____, he saw the tracks of animals in the snow and observed that the appearance of each one was different.
A.while he hunting | B.while hunting |
C.while he hunt | D.while hunted |