one at a time

Cross the road one at a time don't bunch up.

一次一个地过马路--别都挤在一起.

About once a season.

大概一个季度去一次。

We'll have a meeting every month.

咱们一个月碰头一次。

I can only take care of one person at a time.

我一次只能发给一个人。

Once he went to the theatre alone.

有一次，他一个人去看戏。

movement once around a course.

围一个圈绕的一次运动。

bimestrial:Occurring every two months; bimonthly.

一月两次的:每两个月发生一次的;一月两次的。

Occurring every two months;bimonthly.

一月两次的每两个月发生一次的；一月两次的

A nobleman and a merchant once met in a restaurant.

一次，一个贵族在饭店碰到一个商人。

I go jogging three times a week.

我一个星期慢跑三次。

Happening every two months.

每两个月发生一次的

How many stops are there on our route ?

这次车一共有几个站?

Are they in the same class?

是同一个档次的货吗？

4 units from the first purchase

第一次购货的4个单位

an intended trip abroad next month.

下个月的一次出国旅行

Once per session

每个阶段作业比较一次

Need secondary IP address.

需要一个次要 ip 地址。

He carried six boxes at a time.

他一次拿六个盒子。