BULATS has no fixed dates.

BULATS考试没有固定日期。

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Such ceremony has comparatively fixed dates of action and the places of worship, characteristic of earlier astronomical observation of the movement of the sun shadows.

这种仪式有比较固定的行事日期和祭祀场所，带有测度日影的早期天文学观察性质。

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Package is valid for fixed dates departure and return.

适用于指定航班出发及回程。

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Another idea is a formal system of booking operations on fixed dates.

ECONOMIST: Waiting for Dobbo

There are fixed dates for the tests for 11- and 14-year-olds, but test dates are not given out in advance for seven-year-olds, for whom the experience is supposed to be less formal.

BBC: Tests - a guide for parents

In July, the US space agency fixed the dates of its last shuttle flights.

BBC: Nasa Moonship flight target slips