[riverkid]

Originally Posted by muskrat

What is the difference between

I have had a cold for two weeks

and

I have a cold for two weeks

The difference is we don't use the present simple to discuss lengths of time.

We can of course say,

"I have a cold"

because the present simple describes a state, and these states are thought of in English as "timeless". When we want to discuss the amount of time, the length of time that something has been going on, we use present perfect.

I live in Bangkok. I've lived there for 3 years.


What is the active voice of

Smoking has been shown to be dangerous for peoples health

Though we can put the sentence above in the active voice, it wouldn't [necessarily] be that natural. For one thing, I don't know for sure who the subject would be.

Scientists/Researchers/People/Doctors/Health care professionals have shown that smoking is dangerous to peoples' health.


Thanks!!!

You're welcome, Muskrat.