sth is a long time in politics

Hi there,

'a week is too long in politics' means that decisions have been changed so fast in the political scene that one week is a long time.

Within one week, the government's decision has been changed from going one way to going exactly the opposite way (by making another U-turn).

'another' implies that U-turns have been made before. In politics, within one week, things can look very different so a week is a long time as a lot of things have happened.


'by-election' means a special election held in the interval between regular elections to fill a vacancy. 'By-' is a prefix that means secondary or incidental to the main.

I hope you find it useful.

A week is too long in xxx...
意思是xxx的情勢可以在很短時間轉變很大，這跟件事是否在一個星期內改變無關，是一個expression諺語。
意譯是：政治可以是瞬息萬變的。

by-election的by是附加/額外/次要的prefix。不是preposition的by意思。
意思是正規按憲法的大選外而需要安排的「補選」。
另外一些實例：
MTR by-law 地鐵附屬法例
high-ways and by-ways 追上潮流的和小眾一派的 (或直指主要道路和支路的交通幅蓋)
bypass (電子或電力系統的旁路，引伸作越過某種正規程序的捷徑)