La girelle fait partie du tour de potier.

Because faire partie de is the normal French expression for to be part of.

So:

• La girelle fait partie du tour de potier = The wheel head is part of the potter’s wheel

Even though fait literally means does/makes, you should learn faire partie de as a fixed expression meaning to be part of.

You would not normally say La girelle est partie du tour de potier. That is incorrect here.

A few examples:

• Le moteur fait partie de la machine. = The motor is part of the machine.
• Ce chapitre fait partie du livre. = This chapter is part of the book.

Because the subject is La girelle, which is:

• third person
• singular

So the verb faire must be conjugated as fait in the present tense.

Present tense of faire:

• je fais
• tu fais
• il/elle/on fait
• nous faisons
• vous faites
• ils/elles font

Since la girelle = she/it, the correct form is fait.

Girelle is a noun, and in French nouns usually need an article.

Here, la is the feminine singular definite article, meaning the.

So:

• la girelle = the wheel head / the turntable (depending on context)

French uses articles more often than English does, especially in definitions, descriptions, and general statements.

Also, girelle is a feminine noun, which is why it takes la and not le.

Girelle is a specialized pottery term. It refers to a rotating part used on or with a potter’s wheel, often translated as something like wheel head, turntable, or sometimes bat, depending on the exact context.

It is not a very common everyday French word, so many learners will only meet it in pottery or ceramics vocabulary.

The important grammar point is that it is:

• a noun
• feminine
• singular here: la girelle

Because du is the contraction of de + le.

In French:

• de + le = du
• de + les = des

So:

• fait partie de le tour becomes fait partie du tour

This contraction is mandatory in standard French.

Examples:

• le couvercle du pot = the lid of the pot
• la porte du four = the door of the oven

This is a very important distinction.

• tour de potier means potter’s wheel or literally wheel for a potter / wheel used by a potter
• tour du potier means the potter’s wheel in the sense the wheel belonging to the potter

So de potier often describes the type or function of the thing, not possession.

Compare:

• un chapeau de femme = a women’s hat / a hat for women / a woman-style hat
• le chapeau de la femme = the woman’s hat

In your sentence, tour de potier is the established name of the object: potter’s wheel.

Because in tour de potier, the phrase de + noun is being used to describe the type of object.

So:

• tour de potier = potter’s wheel
• literally something like wheel of potter or potter-type wheel

French often leaves out the article in this kind of labeling or classification phrase.

Compare:

• une tasse à café = a coffee cup
• une salle de bain = a bathroom
• un couteau de cuisine = a kitchen knife

So de potier works like a category label, not a full possessive phrase.

Yes. In this sentence, tour is masculine, which is why you see:

• le tour
• du tour

Be careful, because tour can have different meanings in French, such as:

• a turn
• a tower
• a tour
• a wheel / lathe, depending on context

Here, in tour de potier, it means wheel, specifically potter’s wheel.

It can sound a bit like a definitional statement, and French often uses the definite article for that.

So du tour de potier can be understood as:

• part of the potter’s wheel
• or more generally part of a potter’s wheel as an object/type

French uses the definite article much more naturally than English in general statements.

For example:

• Le chat est un animal domestique. = The cat is a domestic animal / Cats are domestic animals.

So here, the sentence may be explaining the structure of the object rather than identifying one particular wheel in a strongly specific way.

A natural pronunciation would sound roughly like:

• fait partie de → fay par-tee duh
• du tour de potier → dy toor duh po-tyay

A few useful points:

• fait sounds like fay
• partie sounds like par-tee
• du sounds like dy with the French u
• potier sounds approximately like po-tyay

In normal speech, French flows together smoothly, so the whole sentence is said as one rhythm group.

Yes, grammatically you could, but it means something slightly different.

• fait partie de = is part of
• appartient à = belongs to

So:

• La girelle fait partie du tour de potier focuses on being a component
• La girelle appartient au tour de potier focuses more on belonging to it

When talking about machine parts or physical components, faire partie de is usually the more natural choice.

The most useful pattern is:

[thing] + fait partie de + [whole]

Examples:

• La poignée fait partie de la porte. = The handle is part of the door.
• Ce bouton fait partie de la machine. = This button is part of the machine.
• Le chapitre 2 fait partie du livre. = Chapter 2 is part of the book.

Also remember these grammar points from your sentence:

• faire partie de = to be part of
• de + le = du
• tour de potier = a type/name expression, so potier does not need an article here