French language Q&A Forum

I have two separate questions regarding the same example 

The first is…why do you use “sa tête” to mean “his face”? 

The second is…I am sure that there are many colloquial ways or common ways to express “should have” using the verb avoir in its conditional conjugated form when it’s not followed by “dû”, but is it actually proper French grammar? For instance, in one of the above examples, it reads: “Tu aurais vu sa tête quand je suis apparu devant lui.”  Its translation is “You should have seen his face when I appeared in front of him.” Possibly contextually it translates better to should than would. Perhaps if the sentence was “ Tu aurais vu sa tête, si tu avais été là.” Then it’s a true conditional statement-You would have seen his face (condition) if you had been there. So perhaps I’ve answered my question because this really isn’t a conditional statement However, I like rules, I like things to follow those rules (The Container Store is one my happy place-quote from Emily in Paris). I also realize that as I write this, the English language is known for not always following grammatical rules in one sense or another (although I can’t think of any because it makes sense to me as a native English speaker, so please forgive my hypocrisy). Please help me understand when avoir in its conditional form means should when not followed by dû.

when i go to my notebook it doesn't let me retake quiz. it just shows what is in my notebook and when i click those lessons i see the same message. i feel like i am going in circles. 

Can I just check the spelling of the second "apparus" in Céline’s reply to Jenny-Anne? 

She says "The correct answer was -  Both sentences are correct 

as you can say  Puis, nous sommes apparus and Puis nous avons apparus"

This sentence was considered correct:  

Tu es apparue comme un ange.

But that doesn't that assume we know that the subject is female?  If we don't know, why isn't it Tu es apparu comme un ange.

The lesson says:

Conjugations of APPARAÎTRE (to appear) in Le Passé

Composé (Indicatif) in French

j'/je

 suis apparu(e)

tu

 es apparu(e)

il / elle / on

 est apparu(e)(s)

nous

 sommes apparu(e)s

For this to be correct, doesn’t the subject have to be female? I answered that only “Tu as apparu comme un ange” was the only correct answer because I couldn’t assume that the sub just was female

This lessons specifically states that: 

To conjugate apparaître in Le Passé Composé (Indicatif), both auxiliaries avoir and être are perfectly valid and interchangeable while the meaning remains the same.  In terms of usage, être is used more often than avoir in colloquial speech.  

I've seen the comments below about one is used more for appearing, but why is mine wrong?

Soudain, j'ai apperu derrière eux

The conjugation that you provide includes the following line:

il / elle / on    est apparu(e)(s)

Under which circumstances would it be valid to have "est apparus" or "est apparues"? Or is the "(s)" redundant?

My comment is similar to Elizabeth's, so I hope your response will also be similar.

My answer to...

À ce moment-là, les étoiles ________ dans le ciel.

was "sont apparus". This is wrong because I didn't know that étoiles is feminine. But the only correction given was "ont apparu".