verb for subject with "multi-"

Hi murwari , SSwami is correct (+1): "wallet" is singular. I think that you may be asking about "currency" vs. "wallet."

Wallet has two adjectives that come before it.

The first one, "multi-currency," may appear to be a noun because currency is a noun. Prefixes such as multi- or mid- (e.g. mid-century, midlife) can change nouns into adjectives.

In addition, English uses "regular" nouns as adjectives (often called "noun-adjectives"): sports car, race horse, horse race, water heater. A race horse is a horse that competes in races. A horse race is a race for horses.

The noun-adjective always comes before the noun that it modifies.

If we see what in this case appears to be
noun + adjective + noun
or
noun + noun (race horse rather than racing horse, e.g.)
we ask whether the first "noun" acts as an adjective.

If so, the second noun is always the subject of the verb. [Multi-]currency must be an adjective because it comes first (and because "multi" makes it an adjective). Wallet, singular, must be the noun.

"That" refers to the wallet. The verb in the clause agrees with the noun to which "that" refers: He wanted to play in the tennis shoes that were red.

Here is a post] by GMATNinja about "that."

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