This seems to be a variation of the idiom "to put one's foot in one's mouth". If you put your foot in your mouth, it means you have said something awkward or embarrassing. If someone says "open your mouth, it's time to switch feet" they probably are referring to the fact that you had already said one embarrassing or awkward thing and have just done it again(or are about to do it again).
It can mean staring, open-mouthed, but is normally used to mean an open fissure or crack
Munching means chewing; it has nothing to do with whether your mouth is open or not.
It means to smile broadly, especially in an unrestrained manner and with the mouth open.
A single pole single throw switch (SPST) is used to open or close a contact to a single wire. It can be used as an on/off switch for an appliance or for a light bulb.
''XD'' means laughing, if you look at it sideways, the X stands for large squinted eyes. The D stands for a mouth open laughing! Get It?
If an anole's mouth is open it wants to mate.
hippos can open there about 3 feet or more depending on the size
Open the mouth wide.
Open your mouth
It can mean staring, open-mouthed, but is normally used to mean an open fissure or crack
Open your mouth
Of course there isn't. Feet can be very sexy. Open your mind...
it means you sleep with your mouth open.
How about trunk. It is open or the switch has been bumped and it thinks its open.
gape
It means your a goos kisser;)
The trunk lid is open or the trunk ajar switch has malfunctionedThe trunk lid is open or the trunk ajar switch has malfunctioned