题干
-What’s wrong with him?
--The picture he came across____ his memory of a sad story in his childhood.
--The picture he came across____ his memory of a sad story in his childhood.
A：set off
B：took off
C：gave off
D：put off
答案(点此获取答案解析）
A
表示双曲线，则实数k适合的条件是