adv.周期性地;定期地,偶尔;
例句:
He drinks far more than she, and is periodically rebuked.
他喝酒比她厉害得多, 为此,有时受到她的责怪.
Invading woody vegetation, especially of the same species, should be controlled periodically to prevent confusion.
入侵的木本植物, 特别是同一种类的, 应当定期地除去,以防止混杂.
Violent winds periodically drive clouds of dust around Mars.
狂风间歇地席卷火星上的尘云.