OG的一篇閱讀 - 英檢

OG p.83

In this newly emerging economic order, workers sometimes organized to protest
their rights and tranditional ways of life. Craftworkers such as carpenters,
printers, and tailors formed unions, and in 1834 individual unions came
together in the National Trades' Union. The labor movement gathered some
momentum in the decade before the Panic times, few workers were willing to
strike or engage in collective action.


6.The phrase gather some momentum in the passage is closest in meaning to

made progress
become active
caused changes
combined forces


答案是第一個 made progress
想請問為何不是第四個 combined forces ?@@
謝謝~

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