Wǒ xiǎng dìng yīgè dài shuāngrén chuáng de biāozhǔn jiān.
I'd like to book a standard room with a double bed.
Tips
usage
In Chinese hotels, 双人床 (double bed) is distinct from 双人间 (a room for two people, which might have two single beds). Be specific when booking to avoid confusion.