书上说：shift the entire spread up to increase the likelihood of buying the base currency, or down to increase the likelihood of selling base.

for example, a dealer who changes her bid-ask in EUR:USD from 1.3 - 1.33 to 1.29 - 1.32, would expecte to buy less euros and to sell more euros, which would decrease her inventory position in euros.

我不明白啊，哪位师兄师姐给我解释一下呢？谢谢！

这段话描述的内容跟现在做空欧元的情形类似。

汇率从 1:1.3 降到 1:1.29 表明欧元换美元在下跌，此时的交易主要为做空欧元，所以dealer会多卖出欧元，上涨的时候做多，下跌的时候做空是最常见的交易手法。

意思是保持中间价不变，你可以调整整个spread的区间上移或下移，看你是想买还是想卖。

比如保持中间价1.3不变，你（这里你就是dealer)想买欧元的时候就报bid 1.29 ask 1.33，但是如若你想卖欧元，则中间价还是1.3你就要报价bid 1.27 ask 1.31，make sense?