Why do we use present continue in context ?

[nininaz]

Hello Dear Teachers,

..However, when the new plants come, they push out other plants. Consequently,
the parks have rules against bringing them in. The only problem is, sometimes we don’t know we’re doing it.
Seeds have so many different ways of traveling. For example, they can float on the wind or on water...
Thanks.

 

[bhaisahab]

It's perfectly correct. What do you think is wrong with it?

 

[nininaz]

I knew It is correct. Because it was extracted form TOEFL IBT book.But I don't know why? Why it used 'present continue' ?What is the usage of this tense here?for example could we use present simple or future or something like that?

 

[bhaisahab]

...for example could we use present simple or future?
No.

 

[nininaz]

So why could we use present continues?

 

[bhaisahab]

So why could we use present continuous?

It's the natural way to say it in English.

 

[Raymott]

The only problem is, sometimes we don’t know we’re doing it.

The only place I can see the present continuous is in "we're doing it", ie. we're bringing in foreign plants.
While we are doing this, we don't know that we are doing it. The introduction of new plants takes time, and the passage is saying that all during this time, we don't know that it's happening. The passage probably ends by saying we should be more careful if we think this is happening.

 

[MikeNewYork]

Did you copy this from a web site? If so, you need to include the source.

Also, is the information in your member info correct?

 

[Matthew Wai]

The source is http://learnenglish.britishcouncil.org/en/english-grammar/verbs/present-tense/present-continuous