Shopping in markets is no source of cheap purchasing unless one is able to keep pace with the apparent mental agility of the vendor.

除非你能跟上小贩异常敏捷的思维，否则在市场上购物是不可能买到便宜东西的。

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His intellect and mental agility have never been in doubt.

他的才智和头脑的敏锐从未被受到怀疑。

《柯林斯英汉双解大词典》

Composing music requires creativity and mental agility.

作曲需要创造力和思维的敏捷。

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There is a long-standing fascination with those who can accomplish astounding feats of mental agility.

BBC: How does a human calculator do it?

On a deeper level mental agility is the capacity to weigh conflicting options, to be able to make hard choices when both options are good, such as which business to buy or which employee to promote.

FORBES: Three Traits Every Great Leader Must Demonstrate

Spontaneity really comes down to mental agility.

FORBES: Three Traits Every Great Leader Must Demonstrate