前 meaning 'before' vs 前 meaning 'first of'

[歐博思]

I came across a sentence on Wechat, and I realized I often question this structure whenever I see it, but  forgot to note where I saw it, so can only convey the general sense of the question below:

 

Say you have a time, 傍晚, or an event， 會....

 

How would one distinguish between the first 5 minutes of the event/time period versus 5 minutes prior to beginning of said period/event?

[skylee]

Say it is a meeting.

會議頭/ 首5分鐘 = first 5 minutes of the meeting

會議前5分鐘 = 5 minutes before the meeting

[歐博思]

Thank you skylee. Would using 的 and 前 together affect meaning? 會議前的5分鐘

[Lianbu Zhou]

会议(的)前五分钟 = The first five minutes of the meeting.

 

会议前（的）五分钟 = Five minutes before the meeting。

 

As you see, it is the 的 changes the meaning of sentence. The 的 is ignored so that the meaning of the sentence differed.

[skylee]

It is all right to use 的.

[masteryoshi]

会议的前5分钟 = first 5 minutes of the meeting
会议前的5分钟 = 5 minutes before the meeting 

[dwq]

But note that if you use 的 in the other case it goes before 頭 or 首。

會議的頭/ 首5分鐘

[ZhangJiang]

Written down it's ambiguous, but spoken, it's 会议'前五分钟 vs. 会议前'五分钟.

You can use other expressions to be specific like 会议之前五分钟 vs. 会议的前五分钟.

However, normally the context clears things up.

[歐博思]

Immensely helpful. Thank you points to all! 

[歐博思]

“把前兩天的睡覺時間補回來了”

 

In the same spirit as my original 前 question, above does this refer to only two days ago, or does it include now until two days ago (including yesterday)? 

[Tiana]

“把前兩天的睡覺時間補回來了”

My interpretation of "前兩天" (= the last few days) is not as specific as yours, so it may not address your question:

"I've / That has made up for the loss of sleep in the last few days"

 

(Actually, I think to attract better response the question may benefit from some clarification.)