Breakdown of Vosotros habéis puesto un cristal nuevo.
vosotros
you all
nuevo
new / another, different (before the noun)
un
a, an, some
poner
to put / to set (the table) / to make (an excuse) / to give, to impose (a fine, a penalty)
Questions & Answers about Vosotros habéis puesto un cristal nuevo.
Why is the word puesto used here instead of ponido?
Puesto is the irregular past participle of the verb poner (to put). Like a few other common verbs you are learning in this lesson, its past participle is irregular and ends in -to instead of the standard -ido ending.
Why does the sentence use habéis?
Habéis is the vosotros (you all) form of the helping verb haber. Because this is Castilian Spanish (spoken in Spain), vosotros habéis is the natural way to say 'you (plural) have'. In most of Latin America, you would say ustedes han instead.
Doesn't cristal just mean crystal? How does it mean a pane of glass?
It can mean crystal, but in everyday Spanish, cristal is the standard word for the glass used in windows, doors, or eyeglasses. A windowpane or a piece of flat glass is very commonly just called un cristal.
Could I say un nuevo cristal instead of un cristal nuevo?
Descriptive adjectives usually go after the noun in Spanish, so un cristal nuevo is the most natural way to talk about a physically new pane of glass. Putting nuevo before the noun sometimes implies it is just a newly acquired replacement (new to you), but putting it after tells us the object itself is brand new.