如图所示的是研究凸透镜成像规律的实验装置图,在蜡烛从P点左侧向F点靠近的过程中,调节光屏的位置,能观察到光屏上烛焰的像逐渐______. (填“变大”、“变小”或“不变”);当蜡烛移动到F点与O点之间时,在光屏上看不到烛焰的实像,这时,怎样观察烛焰的虚像?说出你观察的方法:_________________.
These reference books donated by a non-profitable organization are available for ____ wants to have it.
---Haven’t seen you for ages! Do you still work in Guangzhou? ---______. It’s two years since I worked there.
There was a tree in front of the house, ___ owner was seen sitting under it, enjoying the shade.
Studies show that daydreaming contributes significantly to concentration powers and the ability _____ with others.
______ send officials abroad for training, I think it is better for the government to directly admit people who have studied and worked overseas.