He along the seaside a tsunami came．
A. walked；when
B. is walking；as
C. was walking；when
D. was walking；while
网友回答
A. walked；when
B. is walking；as
(答案→)C. was walking；when
D. was walking；while
解析：考查短语。本题考查be doing …. When …正在做……突然……。句意：他正在沿着海边走突然海啸来了。