园林树木在冬季都进行涂白,涂白的目的是(),延迟树木萌芽,避免日灼危害。
参考答案:防治病虫害
---My brother is a basketball player.
---And he usually_____ very hard on the playground.
A.has practiced
B.is practicing
C.practices
D.practiced
客运列车耽误本列1h以上,为一般A类事故。