想問下面的句子文化上有什麼錯誤~~~

1,Whenever you witness crimes,please inform police as soon as possible.

Whenever you witness (a crime),please inform (the) police as soon as possible.

2,One Of my friend was taken to hispital last month.He died yesterday.

One (of) my friend was taken to (the hospital) last month.He died yesterday.

3,The gangster was arrest for serious organized crimes.

The gangster was (arrested) for serious organized crimes.

4'The audience has just left the concert hall.

The audience has just left the concert hall. This is ok but
The audiences have just left the concert hall. will be better

5)They went for a picnic at CHristmas Day

They went for a picnic (on Christmas) Day(.)

Revised version:

1) Whenever you witness (a) (crime), please inform (the) police as soon as possible.
2) One of my (friends) was taken (into) (the) (hospital) last month. He died yesterday.
3) The gangster was (arrested) for (serious-organized) crimes.
4) The audience has just left the concert hall.
5) They went for a picnic (on the) Christmas Day.

( ) Changed/ New Added

1,Whenever you witness crimes,please inform [the] police as soon as possible.
"the police" 表示警方，因為一般只有一方是警方，所以要用definite article 'the'

2,One Of my friend[s] was taken to hispital last month.He died yesterday.
[One of my] 表示不只一個friend，所以friend 要用眾數 friends

3,The gangster was arrest[ed] for serious organized crimes.
[gangster] 是被抓的對象，所以要用passive voice，而passive voice 的格式是在auxilliary verb 後面用past participle (過去分詞)

4'The audience [have] just left the concert hall.
[Audience] 表示一眾聽眾，已經是眾數，所以要用 have

5)They went for a picnic [on] CHristmas Day.
日子要用[on], 而時間則要用[at] 。

1,Whenever you witness crimes,please inform the police as soon as possible.
2,One Of my friends was taken to hispital last month.He died yesterday.
3,The gangster was arrested for serious organized crimes.
4'The audience have just left the concert hall.
5)They went for a pinic on Christmas Day.

1. Witnessed
2. friends
3. arrested
4. --
5. on