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A few questions about Present Perfect. Do people continue to do thay did before?

not that literally...you have been knowing since but your still engaged thats why

1. Yes
2. Yes
3. Probably
4. Yes, but... "We have known each other FOR 20 years" is better. (We still know each other)

'Already' can be used with past perfect in recently completed actions. (I have already finished my homework). When talking about a continuing amount of time, use FOR. (I have studied English for 5 years, and I'm still studying).

Hope this helps!

Daniel

1) "This man has designed planes since 1985." Question: does the man continue to design planes? Yes, he does.
2) "I have long wanted to visit this city." Do I continue to want? Yes, you do.
3) "He has loved her." Does he love her now? Yes, but without some reference to another time it sounds a little strange. "He has loved her since he was in high school. "
4) "We have known each other for twenty years already." Do we continue to know each other? Yes, we do.


The action continues in all of them. But not all verbs are like that.
"I've read that book." "I've seen that movie." "I've been to New York." (I finished those activities.)

1) Yes, he still designs planes. However, "This man has BEEN DESIGNING planes since 1985" is better.
2) Yes, you do still want to visit or perhaps you have very recently arrived for your first visit to the city.
3) No, he doesn't. He has loved her at some time in the past, we are not sure when. If you say, "He has loved her since the first time he saw her," (for example) then we know he still loves her.
4) "We have known each other for twenty years already." Yes, you still know each other. 'Already' is not necessary here. It suggests that you are surpised by how long you have known each other. It seems like a shorter time than 20 years.