我来回答吧：英语中表示倍数的有以下方式：
拿“A比B大几倍来举例”吧
1.比较级：A is several times bigger than B.
2.同级as...as：A is several times as big as B
3.倍数+ 名词：A is several times the size of B
4.用what：A is several times what B is.
楼主的句子用的是以上中的第三种,只不过比较的是重量（weight）而非大小(size).“带回家的昆虫重量是（以往的）十倍”
楼主如果还是不明白,欢迎追问~