✔ 最佳答案
Only (1) is correct, (2), (3), (4) are incorrect.
If we really want to use [xx] of [xx] instead of [the important point], we probably can say: [the importance] of [this point] is ......Sometimes certain compound nouns, such as [orange juice], can be expressed as [juice] of [orange], and [pork loin] as [loin] of [pork] etc., but not all the time. For example, [Distance Learning] can not be expressed as [Learning] of [distance].
Many [xx] of [xx] take the form of: [noun] of [noun]. Usually the first noun is a function of the second nourn.
e.g.
1) You are [one] of [us].
2) She loves [cream] of [mushoom] soup.
3) The best [part] of [the movie] is the ending.
4. The school is North of here.
Some [xx] of [xx] can take the form of: [adj] of [noun],
e.g.:
1) John is the [smarter] of [the two brothers].
2) He is very [fond] of [Timmy].
3) Little Timmy is [full] of [energy].
Some [xx] of [xx] take the form of: [noun] of [pronoun] *as predicate adjective.
e.g.:
1) He is a friend of mine. (i.e. He is my friend).
2) He is wearing that worn out old shirt of his again. (He is wearing his worn out old shirt again).
[Verb + of] can form many phrasal verbs, in the form of [verb] of [noun] / [noun phrase]:
e.g.
1) This dinning room set [consists] of [6 chairs and a table].
2. This ring is [made] of [gold].
"of" as a preposition, can be used in numerous ways, so the above examples are by no means all inclusive.
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