为了消除 角误差,每站前视、后视距离应___( )____,每测段水准路线的前视距离和后视距离之和应___大致相等___。
You can _____ some bottles of wine, or some chocolates, or a bunch of flowers.
A campus emergency ______ occur at any time of the day or night, weekend, or holiday, with little or no warning.
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