hasincreasedfourtimes是翻成三倍还是四倍?
原句:Accordingtoarecentsurvey,inthepast10years,thenumberofthefamilykeepingpetshasincreasedfourtimes.
我在在线词典里查到的句子:
Theproductionofvariouselectrontubeshasbeenincreasedfourtimesasagainst1958.
各种电子管的产量比1958年增加了3倍.
theoutputhasincreased3timescomparedwith1997
产量比1997年增加了2倍
可网上查查有些类似的也翻成四倍的么,所以搞不懂了,到底我这句原句是翻成3倍还是4倍?