问题
选择题
My grandpa transplants some trees to his garden ________ it is the best time for them every year.
A．where
B．when
C．that
D．until
答案
答案：B
考查状语从句。Where哪里，when当什么的时候，until直到，句意：我爷爷给他的花园移植了一些树，当每年对它们来说是最好的时节。故选B。