A hydrocarbon was known to be either an alkene or alkane.某碳氢化合物已知可能是烯烃或是烷烃.The hydrocarbon must be an alkene.这个碳氢化合物必定是烯烃.The betaine will collapse to the alkene only when these two functions are eclipsed.只有当这两个基团移至重迭位置时...
我得找出是谁企图诬陷我。I need to find out who tried to frame me.他一直举棋不定，找出种种理由不予成交。He kept waffling and finding excuses not to close the deal.她找出一双戴维的袜子穿在了冰冷的脚上。She fished out a pair of David's socks for her cold feet....