Please correct the two sentences

Please correct the two sentences
 

Hello

Could someone please help me correct the following sentences?
or provide better equivalents for the two ones?

- Sexuality and its manifestations constitute some of the most complex of human behavior. The expression of Sexuality and intimacy remains important throughout the life span.

Thanks a lot

The sentences seem to be clear and in correct English. Do you try to translate into Spanish? (I am not an English native speaker but I do not see anything wrong on the grammatical construction of what you wrote.)
Maybe just lower case "sexuality". Otherwise, other English native speakers can say their views.

I agree with JPablo. The English you wrote is clearly understood and correct with the one correction JPablo suggested.

Are you serious? Poli and JPablo?

I think both sentences are incomplete. I am not sure, but the first sentence need something between complex and of

On the second sentence needs to explain a bit more about whose life span...

Am I wrong?

Agreed, you two guys missed that in the first sentence.

As for the second sentence, that would be good, but we're helping him for grammar, not sentence content and substance.

Here's some suggestions from me:

Sexuality and its manifestations constitute some of the most complex parts of human behavior.


Sexuality and its manifestations constitute some of the most complex types of human behavior.

Sexuality and its manifestations constitute some of the most complex facets of human behavior.


All of those above would work... but you need something after complex.

Looking at it again, you could actually just remove 'of' and leave it as:
"Sexuality and its manifestations constitute some of the most complex human behavior."

Thanks everybody for your help
I'm going to translate them from my native language into English
AND what about this part "The expression of sexuality and intimacy remains important throughout the life span"
isn't it correct to say"The expressionS of sexuality and intimacy REMAIN...."

Yes. :)

Well, Chileno, I was serious, when I gave my input.
Before answering, I thought about,
"Sexuality and its manifestations constitute some of the most complex aspects of human behavior."
"Sexuality and its manifestations constitute some of the most complex of human behavior patterns."
As a way to make the sentence 'better', but in looking for "incorrections" I couldn't find any.
I still believe the original sentences are not necessarily "wrong". I fully agree that your suggestion and Wafflestomp's make it better, if that is what the original Farsi (?) from Majidkh said... (No intend on getting into a big argument here, but a Google search of "one of the most complex of" gives 862,000 hits, and searching "one of the most complex of human" I get 11,400,
as in,
Flavour perception is one of the most complex of human behaviours.
I note that in the many "hits" the last word is PLURAL, as in this example above.
Also, another option would be, "one of the most complex of all human behavior".

Again, the last proof of the pudding, Majidkh, is what your original text exactly says...
I hope this is of help! :)

Well, as a native speaker, "some of the most complex of" is totally wrong without something after 'complex'. Just how it is :)

That's why I posted what I posted. (popeye anyone? :))

So, what JPablo wrote "Sexuality and its manifestations constitute some of the most complex of human behavior patterns" is wrong? ;)

Hmm... well, now that I read it over and over a few times.. I have heard it used this way before, but it sounds quite formal and it really isn't the best way to say it. While adding patterns at the end it does sound a lot better though.