kinds of food的food要不要加s以及since的用法,

kinds of food的food要不要加s以及since的用法,
kinds of food的food要不要加s
以及since的用法,

kinds of food的food要不要加s以及since的用法,
不加.
since的四种用法
1) since +过去一个时间点 (如具体的年、月、日期、钟点、1980,last month,half past six).
I have been here since 1989.
2) since +一段时间+ ago
I have been here since five months ago.
3) since +从句
Great changes have taken place since you left.
Considerable time has elapsed since we have been here.
4) It is +一段时间+ since从句
It is two years since I became a postgraduate student.

可以不加

food在这里表整体，不用加S
另：since可表原因，引导原因状语从句。也可作连词使用“至从。。。”用于完成时态

不加
since有两种用法
1.I have not met you since I went to America .

2.It's been ten years since I met you .

可以加，可以不加，看你什么意思。如果加，就表示几种食物。不加则表示这类食物。
since的四种用法
1) since +过去一个时间点 (如具体的年、月、日期、钟点、1980, last month, half past six)。
I have been here since 1989.
2) since +一段时间+ ago
I have bee...

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可以加，可以不加，看你什么意思。如果加，就表示几种食物。不加则表示这类食物。
since的四种用法
1) since +过去一个时间点 (如具体的年、月、日期、钟点、1980, last month, half past six)。
I have been here since 1989.
2) since +一段时间+ ago
I have been here since five months ago.
3) since +从句
Great changes have taken place since you left.
Considerable time has elapsed since we have been here.
4) It is +一段时间+ since从句
It is two years since I became a postgraduate student.
Since还可以表示“因为”，用法同because，语气上比because要弱，意思是既然。。。

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不加S

不是可以不加,而是不可以加.
food的确可以加s,即变复数.但这里kind已经加了s表示复数,所以food绝对不可以加s与之重复.
since主要有两个意思:
1.由于(基本等于because,后面可以接从句.)
2.从......开始.(多用于现在完成时,后面接具体时间.)

不要,因为food不可数

不用加~
since:
副词 1.此后;从那时到现在
She left school three years ago and has worked as a nurse ever since.
2.之前,以前
连词 1.既然;因为,由于
He must have taken the book since it isn't here...

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不用加~
since:
副词 1.此后;从那时到现在
She left school three years ago and has worked as a nurse ever since.
2.之前,以前
连词 1.既然;因为,由于
He must have taken the book since it isn't here.
Since it is so hot, let's go swimming.
2.(常用于现在完成时或过去完成时)自...以来,从...至今
It's been ten years since they married.
She has been living a hard life since her husband died.
since后的动词不同,起止的时间也不同.
"since+非延续性动词的过去式",从该动作发生时算起;"since+非延续动词或状态动词的过去式",从该动作结束时算起;
It's 3 year since he joined the army.(从入伍算起
It's 3 years since he was a soldier. (从他复员即结束作为一名军人的状态算起
It's 3 years since he smoked(从他不抽烟时

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可以加，可以不加
Scientist have learn a great deal about the kinds of foods people need.
科学家对于人们所需的食物种类有了很多的认识。
You choose. Any kinds of food you'd like.
由你们点菜，哪种食品都可以，只要是你们喜欢的。