16. In me eighteenth century, quilting (became a)( common) technique in foe American colonies for the (make) of coverlets (sewed )in floral and geometric designs.
请问became与sewed是否冲突~~~
24. The spearmint plant, (which )grows to about three feet( height), has stalk less leaves and la*, tapering spikes of (flowers )that are (usually) pink or lilac.
答案为C 实在不明白为什么错了~~`请指教~~