My short explanations are:
Liturgy is/are the official public prayers of the church.
We celebrate the Liturgy of the Word and the Liturgy of Eurachrist at every Mass.
Liturgy means a Public work or action of the whole Church.
The Liturgy is the official public prayer of the Church. Prayed at specific hours to sanctify the day. Certain people like Religious and Clergy are required to pray it. However many Lay people also pray it. It can be prayed alone or in community. Some parishes offer Vespers on Sunday evening as a community prayer.
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