Idiom:  To Put on Weight; used as a verb.

First Example:  During the holidays, it is customary for many
Americans to have to a big family dinner that includes a big turkey and
numerous rich desserts.  Because of all
of this rich food, a lot of Americans tend to put on some weight
during the holiday season.

Meaning:  To Put on Weight means to gain weight
or to get fat.  In this example, it is
common for a lot of Americans to eat big family dinners especially during
Christmas and Thanksgiving.  Because they
eat so much food at this time, it is common for a lot of people to gain weight
during the holidays.  This idiom can
apply to any situation where someone wants to point out that someone has gained
weight in a non-offensive manner.  The
idiom is most commonly used as a verb.

Here is another example:

Second Example:  I haven’t seen Elizabeth for a long time.  I heard that she had really put on weight after she gave birth to
her first son.

Meaning:  In
this case, the idiom, To Put on Weight, is
used to point out that Elizabeth had gained weight after her first
pregnancy.  It is common for most women
to gain weight after they have had their first child.  In this example, the idiom is being used as a
verb.

This idiom is from the book “Everyday Idioms – Book One”
which is used in the LSI Intermediate Conversation Class.

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