When I talked with my grandma on the phone, she sounded weak, but by the time we ___ up, her voice had been full of life.
A. were hanging
B. had hung
C. hung
D. would hang
When I talked with my grandma on the phone, she sounded weak, but by the time we ___ up, her voice had been full of life.
A. were hanging
B. had hung
C. hung
D. would hang
C.
考查时态。By the time 后的从句中多用一般现在时和一般过去时。根据该题的语境可以断定答案为:C.