by the subjoined diagrams:

_â_ is pronounced with the mouth very wide open, the uvula raised and
the tongue much lowered.

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O O
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_é, è, i_ and _in_ are articulated with the lips open and the back part
of the mouth gradually closed.

/
/
/
\
\
\

_a, au, ou_ and _on_ are articulated with the back of the mouth open and
the lips gradually closed.

\
\
\
/
/
/

_e, eu, u_ and _un_ are articulated with the back of the mouth and the