Tickets are available on a first come, first served basis.

票先来先买，售完为止。

《牛津词典》

Reservations will be confirmed on a first come first served basis upon receipt of the registration.

我们将在收到您签名的传真后为您保留座位。

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No appointments are available for the Saturday open house and service will be provided on a first come, first served basis.

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Often clubs offer a set number of memberships when they open and people sign up to join largely on a first come, first served basis.

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Restaurant reservations must be made at least a few weeks in advance, while seats at the wine bar can be had on a first-come, first served basis.

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