as soon as

as soon as
as soon as   一…就…
1.              I'll write you as soon as I get there.
2.              我一到那儿，就给你写信。
3.              Let us start as soon as he comes.
4.              等他一来我们就动身。
5.              I gave the alarm as soon as I saw the smoke.
6.              我一看见冒烟，就发出了警报。
7.              As soon as his father went out, the boy ran to the cinema.
8.              爸爸刚出门，那男孩就跑向电影院。
9.              I arranged the flowers in the vase as soon as I came back home.
10.              一回到家里，我就把花在花瓶里插好。
11.              They will post the tickets to me as soon as they receive my cheque.
12.              他们收到我的支票后就立刻把票寄给我。

详解：

once as soon as
两者均为从属连词，引导时间状语从句，都表示主句的动作紧跟在从句的动作之后发生。
•              once:once除表时间外，还表示条件，一般译作“一旦......就......”。
•              他一旦下定决心，就决不会放弃（本句不可用as soon as）。
•              Once he makes up his mind，he’ll never give it up.
•              as soon as:as soon as强调的只是时间，译作“刚......就......”或“一......就......”。
•              我一到北京就写信给你。
•              As soon as I get to Beijing，I’ll write to you.

as<-->as(so) long as