What’s the difference between past tense and The Present Perfect Tense My English teacher’s explanation about the two tenses makes me confused. Please help me!!!

“What”and“which”

what’s the tense of “for many years” The archeologist have been excavating the caves for many years. The archeologist have excavated caves for many years. Which sentence is right?Please help me!!!

What’s the difference between “in all directions”and “from all directions “

should I add “the” Should I add “the “ in front of “teenagers “?

The difference between” contain “and “include “ There’s a sentence in our English book:It’s a round-trip that takes in all the famous tourist spots. Can the phrase “take in “change to “contain “or “include” ? Please help me!!!

What’s the difference between “the same as “and “the same that “ There is an incomplete sentence that “This pan is the same ___I bought yesterday.” My teacher said the word should be “as”,but why can’t I use the word “that “? Please help me!!!

loved and loving In our text book,there is a sentence—“the gift is not something your loved one keeps.” What’s the meaning of your loved one?Can “loved “be changed to ”loving “? Please help me!!!

What’s the difference between “settle in “and “settle down “? As a Chinese English learner,I always lack language environment.So I cannot tell the difference between some similar phrases or words.Neither does my teacher sometimes. Please help me!!