1.
This kind of problem frequently crops up.
这类问题是经常发生的。
2.
There happen earthquakes in Japan frequently.
日本经常发生地震。
3.
That happens frequently.
这样的事情经常发生。
4.
Earthquakes occur frequently in this area.
这一地区经常发生地震。
5.
Riots are of frequent occurrence in this province.
这省经常发生骚乱.
6.
The verbs with a complement of state usually indicate a habitual or completed action.
状态补语说明的动作常常是已经发生的，也可以是经常发生的。
7.
occurring or encountered or experienced or observed frequently or in accordance with regular practice or procedure.
经常发生、碰到、经历或者遵守的，或者与经常性的行为、手续一致。
8.
not frequent; not occurring regularly or at short intervals.
不经常发生；不是有规律的或者间隔短发生的。
9.
But this does not happen often.
但是，这种情况并不经常发生。
10.
There were constant conflicts among policemen and officials.
警察内部和官员内部经常发生摩擦。
11.
There were constant conflicts Between policemen and officials.
警察和官员双方经常发生摩擦。
12.
Such things often happen in times of war.
战争期间这样的事情经常发生。
13.
Dreams may come because of something that has always happened.
梦可能会因某事经常发生而来；
14.
Claims occur frequently in international trade.
国际贸易中经常发生索赔现象。
15.
This often happens to people of your age.
这种情况经常发生在你这样岁数的人。
16.
So being killed by sharks was a common occurrence.
因此被鲨鱼吃掉是经常发生的事。
17.
A neighborhood in which housebreaks are a common occurrence.
经常发生侵入民宅事件的住宅区
18.
That sort of thing is quite occasional and not the rule.
那种事情很偶然，并不经常发生。