I knew how to interpret "as it is" and "as of now" from the sentences, but I didn't know how to use it well.
And I'm not sure if "as it is" and "as of now" are interchangeable.
Please check these sentences below are grammatically correct and natural to be expressed.
1.They have no way but to watch economic decline as it is.
2.They have no way but to watch economic decline as of now.
3.They have no way but to watch economic decline at the present.
4.They have no way but to watch economic decline at current situation.
Then, is it okay if I use expression like "They have no way to overcome economic decline for the present."?
I wanted to make sure whether it's okay to use "for the present" or not if there are no approachable measures.
If you mean "At the present time, they (whoever they are) don't have a way to overcome the current economic decline which exists in their particular area (financial/geographical/business)" then "for the present" is fine. It means that that is the situation right now but suggests that it might change. Note that it doesn't suggest the economic decline might change, only that "they" currently can't overcome the effects of that decline.
"As of now" (which many people don't like) means "from now and continuing into the future for an unspecified period of time, possibly forever".