Piegare vs. curvare vs. flettere
The Italian verbs piegare, curvare, and flettere all translate to the English verb to bend, but they describe different physical actions. Choosing the correct word depends on whether the bending creates a sharp angle or fold, a smooth rounded arc, or involves flexing a body part or an elastic material.
Piegare
The word piegare is the most common translation for to bend or to fold, implying the creation of a crease, a sharp angle, or a distinct change in direction. It is used when bending wire or metal, folding paper or fabric, and can also mean bending something downward by force.
Ho piegato il filo di ferro per fare un gancio.
(I bent the wire to make a hook.)
Non riesco a piegare questo tubo perché il metallo è troppo spesso.
(I cannot bend this pipe because the metal is too thick.)
Il vento forte ha piegato i rami degli alberi verso terra.
(The strong wind bent the tree branches toward the ground.)
Devi piegare le ginocchia per raccogliere le scatole pesanti.
(You must bend your knees to pick up heavy boxes.)
L'uomo ha piegato il foglio a metà per metterlo in tasca.
(The man folded the paper in half to put it in his pocket.)
Curvare
The word curvare means to bend something into a smooth curve or an arc, without creating sharp angles or creases. It is frequently used for bending wood or pipes into rounded shapes, describing a road that turns, or referring to slouching one's posture.
L'artigiano sa come curvare il legno usando il vapore.
(The craftsman knows how to bend the wood using steam.)
La strada inizia a curvare a destra dopo il vecchio ponte.
(The road starts to bend to the right after the old bridge.)
Non devi curvare la schiena mentre guardi lo schermo del computer.
(You must not bend your back while looking at the computer screen.)
Il calore eccessivo ha fatto curvare la lastra di plastica.
(The excessive heat made the plastic sheet bend.)
Gli operai hanno dovuto curvare il binario per seguire il paesaggio.
(The workers had to bend the track to follow the landscape.)
Flettere
The word flettere means to flex or to bend slightly under pressure. It is predominantly used in medical, anatomical, or athletic contexts to describe bending joints and muscles, or in engineering to describe elastic materials that bend but return to their original shape.
Il fisioterapista mi ha chiesto di flettere il braccio lentamente.
(The physiotherapist asked me to bend my arm slowly.)
L'ala dell'aereo è progettata per flettere durante le turbolenze.
(The airplane wing is designed to bend during turbulence.)
Se continui a flettere il righello in questo modo si spezzerà.
(If you keep bending the ruler like this it will break.)
I ginnasti riescono a flettere il corpo in modi incredibili.
(Gymnasts manage to bend their bodies in incredible ways.)
Prima di iniziare a correre è importante flettere le caviglie.
(Before starting to run it is important to flex your ankles.)
Summary
To summarize, use piegare when bending involves creating an angle or a fold, use curvare when bending something into a smooth, rounded arc, and choose flettere when talking about flexing a joint, a muscle, or an elastic material that gives way under pressure.