都 and 在

[bossidy]

I'm confused about the use of two characters in the following sentence:

這兩年你都在做小偷﹐ 偷別的人的東西﹐ 這很不對。

Why is 都 needed? Is it basically being used to convey the sense that he spent ALL of the last two years being a thief? Does the sentence meaning change if 都 is removed?

What is the function of 在? I can't see why it is needed?

Thanks.

[HashiriKata]

Does the sentence meaning change if 都 is removed?

No, the basic meaning won't change but some of the emphasis will be removed.

What is the function of 在? I can't see why it is needed?

在 here shows that some action/ activity has been going on; without 在 the sentence will be just a general statement and miss out the indication of this continuous / repeating aspect.

[Meng Lelan]

The 都 is telling you that all that time for two years the guy was doing some particular action or being something.

[natra]

在 here is functioning as 正在. It is sometimes translated as "in the process of" or "in the course of."

Here is another example of 正在：

他们正在聊天。(They are having a chat.)

This could also be rendered as:

他们在聊天。

Concerning 都, I think that it gives the original sentence a sense that he has not done just one or two acts of theft in these two years, but has been continually engaged in acts of stealing or theft during this time.

[Lim_zhao]

Why is 都 needed? Is it basically being used to convey the sense that he spent ALL of the last two years being a thief?---It is right for your explanation. "都” means always "一直“ and never change to other job.

Does the sentence meaning change if 都 is removed? If we remove"都”， then the meaning is same, however the tone is changed, Originally we stress that" in last 2 years, he always being as a thief"

What is the function of 在? I can't see why it is needed?------Actually, it can be removed if we use in the written Chinese. But for oral Chinese, we will use "在”， it just is a habit!

[user111]

Think of it as "have been".

[Shi Tong]

bossidy, as others have said, it's basically to create more emphasis, If you said 這兩年你做小偷, it would mean "these two years you've been a thief", but, 這兩年你都在做小偷 means "these two years you've always been being a thief".