frequent

动词 frequent:

1. do one's shopping at; do business with; be a customer or client of
   同义词：patronize, patronise, shop, shop at, buy at, sponsor
2. be a regular or frequent visitor to a certain place
   同义词：haunt

形容词 frequent:

1. coming at short intervals or habitually
2. frequently encountered;

1. His frequent hesitations annoyed the audience.
   他三番五次欲言又止，听众已感到厌烦。
2. He suffers from frequent bouts of depression.
   他患多发性抑郁症。
3. The factory is in frequent scarcity of raw materials.
   这个工厂经常原料不足。
4. Production in the factories stopped because of frequent power failures.
   频繁的停电使工厂停产。
5. These woods are frequented by all kinds of birds.
   这些树林里经常栖息着各种鸟类。
6. The police visited all the bars that the suspect frequented.
   警察调查了嫌疑犯时常出没的所有酒吧。
7. He is a frequent visitor to our house.
   他是我们家的常客。

fre.quent

adj.（形容词）
Occurring or appearing quite often or at close intervals:
经常的：时常或间歇很短的发生或出现：
例句：
frequent errors of judgment.
判断中经常出现的错误

v.tr.（及物动词）
fre.quent.ed,fre.quent.ing,fre.quents也作 [frô-kwμnt.]
To pay frequent visits to; be in or at often:
时常出入：频繁的访问；经常在那儿或常常出现：
例句：
frequent a restaurant.
常去的饭馆

来源：
Middle English [ample, profuse]
中古英语 [丰富的，频繁的]
from Old French
源自 古法语
from Latin frequôns frequent- [crowded, numerous, frequent]
源自 拉丁语 frequôns frequent- [拥挤的，无数的，挤满的]

【引伸】
fre.quenta.tion
n.（名词）
frequent.er
fre.quentness
n.（名词）