LG W5220C Guide De L'utilisateur page 194

Additional Functions
2-1 Making a Second Call
You can make a second call while you are already in a call. To do
this, enter the second number and press [Send]. When you get
second call the first call is automatically put on hold. You can swap
between calls by selecting the [Options] key then Swap.
2-2 Setting up a Multiparty Call
You can connect a call on hold to the currently active call to form a
multiparty call by selecting the [Options] key then Multiparty/Join
all.
2-3 Putting the Multiparty Call on Hold
To put a multiparty call on hold, select the [Options] key then
Multiparty/Hold all.
2-4 De-activate the Multiparty Call on Hold
To de-activate a multiparty call on hold, select the [Options] key then
Multiparty/Join all.
2-5 Adding Calls to the Multiparty Call
To join an active call to the held multiparty call, select the [Options]
key then Multiparty/Join all.
2-6 Displaying Callers in a Multiparty Call
To scroll through the numbers of the callers who make up a
multiparty call on the handset screen, press U and D keys.
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