My parents were quarrelling about me I could not quite tell why.
A. since
B. though
C. if
D. until
网友回答
A. since
B. though
C. if
D. until
解析:though引导让步状语从句,意为“虽然”,表示虽然不知道父母为什么为自己而争吵。since引导原因状语从句或时间状语从句,意为“因为”或“自从”。if引导条件状语从句,意为“如果”。until引导时间状语从句,意为“一直”。