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to be added to; to be appended
to join in (e.g. a group of friends); to participate
to increase (e.g. heat); to gain in (e.g. influence); to grow; to gather (speed)
to be applied (e.g. heat, pressure); to be exerted
新しいメンバーが加わりました。
A new member has been added.
このグループに加わりたいです。
I want to join this group.
新しいメンバーが加わった。
A new member joined.