The leaves turning red and yellow are beautiful. -- This sentence is correct.
The subject of the sentence = the leaves. This is a plural subject - more than one. The subject and verb must agree, this means if you have a plural subject you must have a plural verb form. The plural verb in this sentence is 'are'.
The leaves' turning red and yellow is beautiful. -- This sentence is not correct
'Is' is not a plural verb it is a singular verb.
The main clause in this sentence is -- 'The leaves are beautiful'
'turning red and brown' -- is a subordinate clause
"My beautiful cousins" is indeed a perfectly grammatical phrase. It is, of course, not a complete sentence.
In a sentence grammar can be endings or spelling
The grammar of this sentence is beyond phenomenal.
No. It should be "Is the grammar right in this sentence?"
The same grammar can be implemented by different file formats
no_____If the sentence is You do do that (meaning You are in the habit of doing that) the grammar is perfectly correct and the sentence 'does have correct grammar'.
This is grammatically wrong. But it's lyrics, so just let it be. Actually, the grammar of verse may be different from the grammar of prose. In this sentence, the relative pronoun "who" is understood.
She studied grammar to improve her writing skills.
Chinese grammar/syntax is different from English grammar/syntax. Breaking up an English sentence like that and asking for its Chinese equivalent is not advisable as there may be none. Best to give the whole sentence.
If you are writing proper grammar you should not use 'then' at the beginning of a sentence.
No.
sentence