it have been necessary 和 it is necessary 的區(qū)別?
那你幫我看下這句話(huà)好嗎？這句話(huà)有點(diǎn)長(zhǎng)，這里的necessary,是不是虛擬語(yǔ)氣，如果是虛擬語(yǔ)氣，為何前面沒(méi)有你所說(shuō)的would?只是it had been necessary.而不是it would have been necessary?
But rich planterswere few in the young county of Clayton,and,inorder to muster a full-strength troop,it had been necessary to raise more recruitsamong the sons of small farmers,hunters in the backwoods,swamp trappers,Crackersand,in a very few cases,even poor whites,if they were above the average oftheir class.