Unless the weather ______, we'll have to cancel the picnic.
A：improve
B：improves
C：improved
D：will improve
—How is your grandma?
—She is fine. She used to____ TV at home after supper. But now she is used to____out for a walk.
判断正误。
“落红不是无情物，化作春泥更护花”，请从生态学角度分析，在落红化作“春泥”的过程中，起决定作用的是（ ）
